Bugs fixing: use patch to update status and set default GC period

1. Use patch rather status patch in backup sync controller as we have disable status as sub resource
2. Set the GC period with default value if it isn't set

Signed-off-by: Wenkai Yin(尹文开) <yinw@vmware.com>

pkg/controller/backup_sync_controller.go

@@ -337,7 +337,7 @@ func (c *backupSyncController) run() {
 		// update the location's last-synced time field
 		statusPatch := client.MergeFrom(location.DeepCopy())
 		location.Status.LastSyncedTime = &metav1.Time{Time: time.Now().UTC()}
-		if err := c.kbClient.Status().Patch(context.Background(), &location, statusPatch); err != nil {
+		if err := c.kbClient.Patch(context.Background(), &location, statusPatch); err != nil {
 			log.WithError(errors.WithStack(err)).Error("Error patching backup location's last-synced time")
 			continue
 		}

pkg/controller/gc_controller.go

@@ -79,7 +79,7 @@ func NewGCController(
 
 	c.syncHandler = c.processQueueItem
 	c.resyncPeriod = frequency
-	if c.resyncPeriod < 0 {
+	if c.resyncPeriod <= 0 {
 		c.resyncPeriod = defaultGCFrequency
 	}
 	logger.Infof("Garbage collection frequency: %s", c.resyncPeriod.String())