vendor: opencontainers/selinux v1.5.2

full diff: https://github.com/opencontainers/selinux/compare/v1.5.1...v1.5.2

- Implement FormatMountLabel unconditionally
  Implementing FormatMountLabel on situations built without selinux
  should be possible; the context will be ignored if no SELinux is available.
- Remote potential race condition, where mcs label is freed
  Theorectially if you do not change the MCS Label then we free it and two
  commands later reserve it. If some other process was grabbing MCS Labels
  at the same time, the other process could get the same label.

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

vendor/github.com/opencontainers/selinux/go-selinux/label/label_stub.go

@@ -15,10 +15,6 @@ func GenLabels(options string) (string, string, error) {
 	return "", "", nil
 }
 
-func FormatMountLabel(src string, mountLabel string) string {
-	return src
-}
-
 func SetFileLabel(path string, fileLabel string) error {
 	return nil
 }