ar8031/8033/phy:enable autonegotiation for ar8031/8033

Function "genphy_parse_link()" used "if (mii_reg & BMSR_ANEGCAPABLE)" before
while "if (phydev->supported & SUPPORTED_Autoneg)" now.
So assign "phydev->supported" to "phydev->drv->features" for ar8031/8033
to enable autonegotiation.

Signed-off-by: Zhao Qiang <B45475@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>