net: phy: don't set autoneg if it's not supported

In phy_device_create() we set phydev->autoneg = 1. This isn't changed
even if the PHY doesn't support autoneg. This seems to affect very
few PHY's, and they disable phydev->autoneg in their config_init
callback. So it's more of an improvement, therefore net-next.
The patch also wouldn't apply to older kernel versions because the
link mode bitmaps have been introduced recently.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/phy_device.c

@@ -2149,6 +2149,10 @@ static int phy_probe(struct device *dev)
 	if (err)
 		goto out;
 
+	if (!linkmode_test_bit(ETHTOOL_LINK_MODE_Autoneg_BIT,
+			       phydev->supported))
+		phydev->autoneg = 0;
+
 	if (linkmode_test_bit(ETHTOOL_LINK_MODE_1000baseT_Half_BIT,
 			      phydev->supported))
 		phydev->is_gigabit_capable = 1;