net/cadence/macb: fix invalid 0 return if no phy is discovered on mii init

Replace misleading -1 (-EPERM) by a more appropriate return code (-ENXIO)
in macb_mii_probe function.
Save macb_mii_probe return before branching to err_out_unregister to avoid
erronous 0 return.
Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/cadence/macb.c

@@ -276,7 +276,7 @@ static int macb_mii_probe(struct net_device *dev)
 	phydev = phy_find_first(bp->mii_bus);
 	if (!phydev) {
 		netdev_err(dev, "no PHY found\n");
-		return -1;
+		return -ENXIO;
 	}
 
 	pdata = dev_get_platdata(&bp->pdev->dev);
@@ -379,9 +379,9 @@ int macb_mii_init(struct macb *bp)
 	if (err)
 		goto err_out_free_mdio_irq;
 
-	if (macb_mii_probe(bp->dev) != 0) {
+	err = macb_mii_probe(bp->dev);
+	if (err)
 		goto err_out_unregister_bus;
-	}
 
 	return 0;