ieee802154: 6lowpan: fix return of netdev notifier

This patch fixed the return value of netdev notifier. If the command is
a don't care a NOTIFY_DONE should be returned. If the command matched a
NOTIFY_OK should be returned.
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/ieee802154/6lowpan/core.c

@@ -207,7 +207,7 @@ static int lowpan_device_event(struct notifier_block *unused,
 	struct net_device *wdev = netdev_notifier_info_to_dev(ptr);
 
 	if (wdev->type != ARPHRD_IEEE802154)
-		goto out;
+		return NOTIFY_DONE;
 
 	switch (event) {
 	case NETDEV_UNREGISTER:
@@ -219,11 +219,10 @@ static int lowpan_device_event(struct notifier_block *unused,
 			lowpan_dellink(wdev->ieee802154_ptr->lowpan_dev, NULL);
 		break;
 	default:
-		break;
+		return NOTIFY_DONE;
 	}
 
-out:
-	return NOTIFY_DONE;
+	return NOTIFY_OK;
 }
 
 static struct notifier_block lowpan_dev_notifier = {