net: phy: use genphy_read_abilities in genphy driver

Currently the genphy driver populates phydev->supported like this:
First all possible feature bits are set, then genphy_config_init()
reads the available features from the chip and remove all unsupported
features from phydev->supported. This can be simplified by using
genphy_read_abilities().
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/phy_device.c

@@ -2284,8 +2284,7 @@ static struct phy_driver genphy_driver = {
 	.phy_id_mask	= 0xffffffff,
 	.name		= "Generic PHY",
 	.soft_reset	= genphy_no_soft_reset,
-	.config_init	= genphy_config_init,
-	.features	= PHY_GBIT_ALL_PORTS_FEATURES,
+	.get_features	= genphy_read_abilities,
 	.aneg_done	= genphy_aneg_done,
 	.suspend	= genphy_suspend,
 	.resume		= genphy_resume,