bump opencontainers/selinux v1.2.2

full diff: https://github.com/opencontainers/selinux/compare/v1.2.1...v1.2.2

- opencontainers/selinux#51 Older kernels do not support keyring labeling

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

vendor/github.com/opencontainers/selinux/go-selinux/selinux_linux.go

@@ -406,7 +406,14 @@ func SocketLabel() (string, error) {
 // SetKeyLabel takes a process label and tells the kernel to assign the
 // label to the next kernel keyring that gets created
 func SetKeyLabel(label string) error {
-	return writeCon("/proc/self/attr/keycreate", label)
+	err := writeCon("/proc/self/attr/keycreate", label)
+	if os.IsNotExist(err) {
+		return nil
+	}
+	if label == "" && os.IsPermission(err) && !GetEnabled() {
+		return nil
+	}
+	return err
 }
 
 // KeyLabel retrieves the current kernel keyring label setting