Adding kube pod and container labels to containerd

Currently we have the pod and container labels part of
containerd metadata extensions. However for third party users
like cadvisor that depend on standard kube labels will need
to be aware of the way metadata is stored in containerd to
fetch the labels.

Signed-off-by: abhi <abhi@docker.com>

pkg/server/helpers.go

@@ -381,3 +381,13 @@ func isInCRIMounts(dst string, mounts []*runtime.Mount) bool {
 func filterLabel(k, v string) string {
 	return fmt.Sprintf("labels.%q==%q", k, v)
 }
+
+// buildLabel builds the labels from config to be passed to containerd
+func buildLabels(configLabels map[string]string, containerType string) map[string]string {
+	labels := make(map[string]string)
+	for k, v := range configLabels {
+		labels[k] = v
+	}
+	labels[containerKindLabel] = containerType
+	return labels
+}