xgene: get_phy_device() doesn't return NULL anymore

BugLink: https://launchpad.net/bugs/1632739

Now that get_phy_device() no longer returns NULL on error, we don't need
to check for it...
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit fb1116ab yakkety)
Signed-off-by: Craig Magina <craig.magina@canonical.com>
Acked-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>

drivers/net/ethernet/apm/xgene/xgene_enet_hw.c

@@ -824,7 +824,7 @@ static int xgene_mdiobus_register(struct xgene_enet_pdata *pdata,
 		return -EINVAL;
 
 	phy = get_phy_device(mdio, phy_id, false);
-	if (!phy || IS_ERR(phy))
+	if (IS_ERR(phy))
 		return -EIO;
 
 	ret = phy_device_register(phy);