Simplify comparison to bool constant (gosimple)

This fixes:
build.go:553:6: should omit comparison to bool constant, can be simplified to !strings.Contains(path, ".sha256") (S1002)
pkg/cmd/grafana-cli/commands/ls_command.go:27:5: should omit comparison to bool constant, can be simplified to !pluginDirInfo.IsDir() (S1002)
pkg/components/dynmap/dynmap_test.go:24:5: should omit comparison to bool constant, can be simplified to !value (S1002)
pkg/components/dynmap/dynmap_test.go:122:14: should omit comparison to bool constant, can be simplified to b (S1002)
pkg/components/dynmap/dynmap_test.go:125:14: should omit comparison to bool constant, can be simplified to !b (S1002)
pkg/components/dynmap/dynmap_test.go:128:14: should omit comparison to bool constant, can be simplified to !b (S1002)
pkg/models/org_user.go:51:5: should omit comparison to bool constant, can be simplified to !(*r).IsValid() (S1002)
pkg/plugins/datasource/wrapper/datasource_plugin_wrapper_test.go:77:12: should omit comparison to bool constant, can be simplified to !haveBool (S1002)
pkg/services/alerting/conditions/evaluator.go:23:9: should omit comparison to bool constant, can be simplified to !reducedValue.Valid (S1002)
pkg/services/alerting/conditions/evaluator.go:48:5: should omit comparison to bool constant, can be simplified to !reducedValue.Valid (S1002)
pkg/services/alerting/conditions/evaluator.go:91:5: should omit comparison to bool constant, can be simplified to !reducedValue.Valid (S1002)
pkg/services/alerting/conditions/query.go:56:6: should omit comparison to bool constant, can be simplified to !reducedValue.Valid (S1002)
pkg/services/alerting/extractor.go:107:20: should omit comparison to bool constant, can be simplified to !enabled.MustBool() (S1002)
pkg/services/alerting/notifiers/telegram.go:222:41: should omit comparison to bool constant, can be simplified to this.UploadImage (S1002)
pkg/services/sqlstore/apikey.go:58:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/apikey.go:72:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/dashboard.go:66:33: should omit comparison to bool constant, can be simplified to !cmd.Overwrite (S1002)
pkg/services/sqlstore/dashboard.go:175:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/dashboard.go:311:13: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/dashboard.go:444:12: should omit comparison to bool constant, can be simplified to !exists (S1002)
pkg/services/sqlstore/dashboard.go:472:12: should omit comparison to bool constant, can be simplified to !exists (S1002)
pkg/services/sqlstore/dashboard.go:554:32: should omit comparison to bool constant, can be simplified to !cmd.Overwrite (S1002)
pkg/services/sqlstore/dashboard_snapshot.go:83:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/plugin_setting.go:39:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/quota.go:34:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/quota.go:111:6: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/quota.go:136:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/quota.go:213:6: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/temp_user.go:129:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/user.go:157:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/user.go:182:5: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/user.go:191:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/user.go:212:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/services/sqlstore/user.go:307:12: should omit comparison to bool constant, can be simplified to !has (S1002)
pkg/social/generic_oauth.go:185:5: should omit comparison to bool constant, can be simplified to !s.extractToken(&data, token) (S1002)
pkg/tsdb/mssql/mssql.go:148:39: should omit comparison to bool constant, can be simplified to ok (S1002)
pkg/tsdb/mssql/mssql.go:212:6: should omit comparison to bool constant, can be simplified to !query.Model.Get("fillNull").MustBool(false) (S1002)
pkg/tsdb/mssql/mssql.go:247:56: should omit comparison to bool constant, can be simplified to ok (S1002)
pkg/tsdb/mssql/mssql.go:274:7: should omit comparison to bool constant, can be simplified to !exist (S1002)
pkg/tsdb/mssql/mssql.go:282:8: should omit comparison to bool constant, can be simplified to !exist (S1002)
pkg/tsdb/mysql/mysql.go:221:6: should omit comparison to bool constant, can be simplified to !query.Model.Get("fillNull").MustBool(false) (S1002)
pkg/tsdb/mysql/mysql.go:256:56: should omit comparison to bool constant, can be simplified to ok (S1002)
pkg/tsdb/mysql/mysql.go:283:7: should omit comparison to bool constant, can be simplified to !exist (S1002)
pkg/tsdb/mysql/mysql.go:291:8: should omit comparison to bool constant, can be simplified to !exist (S1002)
pkg/tsdb/postgres/postgres.go:134:39: should omit comparison to bool constant, can be simplified to ok (S1002)
pkg/tsdb/postgres/postgres.go:201:6: should omit comparison to bool constant, can be simplified to !query.Model.Get("fillNull").MustBool(false) (S1002)
pkg/tsdb/postgres/postgres.go:236:56: should omit comparison to bool constant, can be simplified to ok (S1002)
pkg/tsdb/postgres/postgres.go:263:7: should omit comparison to bool constant, can be simplified to !exist (S1002)
pkg/tsdb/postgres/postgres.go:271:8: should omit comparison to bool constant, can be simplified to !exist (S1002)

pkg/tsdb/postgres/postgres.go

@@ -131,7 +131,7 @@ func (e PostgresQueryEndpoint) getTypedRowData(rows *core.Rows) (tsdb.RowValues,
 	// convert types not handled by lib/pq
 	// unhandled types are returned as []byte
 	for i := 0; i < len(types); i++ {
-		if value, ok := values[i].([]byte); ok == true {
+		if value, ok := values[i].([]byte); ok {
 			switch types[i].DatabaseTypeName() {
 			case "NUMERIC":
 				if v, err := strconv.ParseFloat(string(value), 64); err == nil {
@@ -198,7 +198,7 @@ func (e PostgresQueryEndpoint) transformToTimeSeries(query *tsdb.Query, rows *co
 	fillValue := null.Float{}
 	if fillMissing {
 		fillInterval = query.Model.Get("fillInterval").MustFloat64() * 1000
-		if query.Model.Get("fillNull").MustBool(false) == false {
+		if !query.Model.Get("fillNull").MustBool(false) {
 			fillValue.Float64 = query.Model.Get("fillValue").MustFloat64()
 			fillValue.Valid = true
 		}
@@ -233,7 +233,7 @@ func (e PostgresQueryEndpoint) transformToTimeSeries(query *tsdb.Query, rows *co
 		}
 
 		if metricIndex >= 0 {
-			if columnValue, ok := values[metricIndex].(string); ok == true {
+			if columnValue, ok := values[metricIndex].(string); ok {
 				metric = columnValue
 			} else {
 				return fmt.Errorf("Column metric must be of type char,varchar or text, got: %T %v", values[metricIndex], values[metricIndex])
@@ -260,7 +260,7 @@ func (e PostgresQueryEndpoint) transformToTimeSeries(query *tsdb.Query, rows *co
 			}
 
 			series, exist := pointsBySeries[metric]
-			if exist == false {
+			if !exist {
 				series = &tsdb.TimeSeries{Name: metric}
 				pointsBySeries[metric] = series
 				seriesByQueryOrder.PushBack(metric)
@@ -268,7 +268,7 @@ func (e PostgresQueryEndpoint) transformToTimeSeries(query *tsdb.Query, rows *co
 
 			if fillMissing {
 				var intervalStart float64
-				if exist == false {
+				if !exist {
 					intervalStart = float64(tsdbQuery.TimeRange.MustGetFrom().UnixNano() / 1e6)
 				} else {
 					intervalStart = series.Points[len(series.Points)-1][1].Float64 + fillInterval