net: phy: marvell10g: Use the generic C45 helper to read the 2110 features

Contrary to the 3310, the 2110 PHY correctly reports it's 2.5G/5G
abilities. We can therefore use the genphy_c45_pma_read_abilities helper
to build the list of features.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>