libpod: fix a few minor staticcheck warnings

These:

> libpod/container_copy_common.go:34:16: QF1011: could omit type bool from declaration; it will be inferred from the right-hand side (staticcheck)
> 		locked       bool = true
> 		             ^
> libpod/container_internal_common.go:793:3: QF1006: could lift into loop condition (staticcheck)
> 		if maxSymLinks > 40 {
> 		^
> libpod/oci_conmon_linux.go:170:2: QF1007: could merge conditional assignment into variable declaration (staticcheck)
> 	mustCreateCgroup := true
> 	^

Should not result in any change of logic.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

libpod/container_copy_common.go

@@ -31,7 +31,7 @@ func (c *Container) copyFromArchive(path string, chown, noOverwriteDirNonDir boo
 		unmount      func()
 		cleanupFuncs []func()
 		err          error
-		locked       bool = true
+		locked       = true
 	)
 
 	// Make sure that "/" copies the *contents* of the mount point and not

libpod/container_internal_common.go

@@ -788,12 +788,9 @@ func (c *Container) isWorkDirSymlink(resolvedPath string) bool {
 	// If so, that's a valid use case: return nil.
 
 	maxSymLinks := 0
-	for {
-		// Linux only supports a chain of 40 links.
-		// Reference: https://github.com/torvalds/linux/blob/master/include/linux/namei.h#L13
-		if maxSymLinks > 40 {
-			break
-		}
+	// Linux only supports a chain of 40 links.
+	// Reference: https://github.com/torvalds/linux/blob/master/include/linux/namei.h#L13
+	for maxSymLinks <= 40 {
 		resolvedSymlink, err := os.Readlink(resolvedPath)
 		if err != nil {
 			// End sym-link resolution loop.

libpod/oci_conmon_linux.go

@@ -167,11 +167,7 @@ func (r *ConmonOCIRuntime) withContainerSocketLabel(ctr *Container, closure func
 // moveConmonToCgroupAndSignal gets a container's cgroupParent and moves the conmon process to that cgroup
 // it then signals for conmon to start by sending nonce data down the start fd
 func (r *ConmonOCIRuntime) moveConmonToCgroupAndSignal(ctr *Container, cmd *exec.Cmd, startFd *os.File) error {
-	mustCreateCgroup := true
-
-	if ctr.config.NoCgroups {
-		mustCreateCgroup = false
-	}
+	mustCreateCgroup := !ctr.config.NoCgroups
 
 	// If cgroup creation is disabled - just signal.
 	switch ctr.config.CgroupsMode {