gianfar: Handle error code at MAC address change

Handle return error code of eth_mac_addr();

Fixes: 3d23a05c ("gianfar: Enable changing mac addr when if up")
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/gianfar.c

@@ -363,7 +363,11 @@ static void gfar_set_mac_for_addr(struct net_device *dev, int num,
 
 static int gfar_set_mac_addr(struct net_device *dev, void *p)
 {
-	eth_mac_addr(dev, p);
+	int ret;
+
+	ret = eth_mac_addr(dev, p);
+	if (ret)
+		return ret;
 
 	gfar_set_mac_for_addr(dev, 0, dev->dev_addr);