vendor: update c/common

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>

vendor/github.com/opencontainers/cgroups/config_ifprio_map.go

@@ -0,0 +1,14 @@
+package cgroups
+
+import (
+	"fmt"
+)
+
+type IfPrioMap struct {
+	Interface string `json:"interface"`
+	Priority  int64  `json:"priority"`
+}
+
+func (i *IfPrioMap) CgroupString() string {
+	return fmt.Sprintf("%s %d", i.Interface, i.Priority)
+}