usbnet: mcs7830: apply usbnet_link_change

This patch uses the introduced usbnet_link_change() to handle
link change.
Signed-off-by: NMing Lei <ming.lei@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/usb/mcs7830.c

@@ -576,10 +576,7 @@ static void mcs7830_status(struct usbnet *dev, struct urb *urb)
 		 */
 		if (data->link_counter > 20) {
 			data->link_counter = 0;
-			if (link)
-				netif_carrier_on(dev->net);
-			else
-				netif_carrier_off(dev->net);
+			usbnet_link_change(dev, link, 0);
 			netdev_dbg(dev->net, "Link Status is: %d\n", link);
 		}
 	} else