storage: use race-free AddNames instead of SetNames

Commits from parallel builds using `SetNames` removes `names` from
storage for other builds.

Use race-free atomic `AddNames` to prevent breaking of parallel builds.

Signed-off-by: Aditya R <arajan@redhat.com>

storage/storage_image.go

@@ -1197,21 +1197,18 @@ func (s *storageImageDestination) Commit(ctx context.Context, unparsedToplevel t
 		}
 		logrus.Debugf("saved image metadata %q", string(metadata))
 	}
-	// Set the reference's name on the image.  We don't need to worry about avoiding duplicate
-	// values because SetNames() will deduplicate the list that we pass to it.
-	if name := s.imageRef.DockerReference(); len(oldNames) > 0 || name != nil {
+	// Adds the reference's name on the image.  We don't need to worry about avoiding duplicate
+	// values because AddNames() will deduplicate the list that we pass to it.
+	if name := s.imageRef.DockerReference(); name != nil {
 		names := []string{}
 		if name != nil {
 			names = append(names, name.String())
 		}
-		if len(oldNames) > 0 {
-			names = append(names, oldNames...)
+		if err := s.imageRef.transport.store.AddNames(img.ID, names); err != nil {
+			logrus.Debugf("error adding names %v on image %q: %v", names, img.ID, err)
+			return errors.Wrapf(err, "adding names %v on image %q", names, img.ID)
 		}
-		if err := s.imageRef.transport.store.SetNames(img.ID, names); err != nil {
-			logrus.Debugf("error setting names %v on image %q: %v", names, img.ID, err)
-			return errors.Wrapf(err, "setting names %v on image %q", names, img.ID)
-		}
-		logrus.Debugf("set names of image %q to %v", img.ID, names)
+		logrus.Debugf("add names of image %q to %v", img.ID, names)
 	}
 
 	commitSucceeded = true