net: lan743x: Return PTR_ERR() for fixed_phy_register()

fixed_phy_register() returns -EPROBE_DEFER, -EINVAL and -EBUSY,
etc, in addition to -EIO. The Best practice is to return these
error codes with PTR_ERR().
Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/microchip/lan743x_main.c

@@ -1515,7 +1515,7 @@ static int lan743x_phy_open(struct lan743x_adapter *adapter)
 							    &fphy_status, NULL);
 				if (IS_ERR(phydev)) {
 					netdev_err(netdev, "No PHY/fixed_PHY found\n");
-					return -EIO;
+					return PTR_ERR(phydev);
 				}
 			} else {
 				goto return_error;