net: phy: marvell10g: remove XGMII as an option for 88x3310

Remove XGMII as an option for the 88x3310 PHY driver, as the PHY doesn't
support XGMII's 32-bit data lanes.  It supports USXGMII, which is not
XGMII, but a single-lane serdes interface - see
https://developer.cisco.com/site/usgmii-usxgmii/

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/marvell10g.c

@@ -84,7 +84,6 @@ static int mv3310_config_init(struct phy_device *phydev)
 
 	/* Check that the PHY interface type is compatible */
 	if (phydev->interface != PHY_INTERFACE_MODE_SGMII &&
-	    phydev->interface != PHY_INTERFACE_MODE_XGMII &&
 	    phydev->interface != PHY_INTERFACE_MODE_XAUI &&
 	    phydev->interface != PHY_INTERFACE_MODE_RXAUI &&
 	    phydev->interface != PHY_INTERFACE_MODE_10GKR)