Merge branch 'xpcs-phylink_pcs_ops'

Vladimir Oltean says:

====================
Convert xpcs to phylink_pcs_ops

Background: the sja1105 DSA driver currently drives a Designware XPCS
for SGMII and 2500base-X, and it would be nice to reuse some code with
the xpcs module. This would also help consolidate the phylink_pcs_ops,
since the only other dedicated PCS driver, currently, is the lynx_pcs.

Therefore, this series makes the xpcs expose the same kind of API that
the lynx_pcs module does. The main changes are getting rid of struct
mdio_xpcs_ops, being compatible with struct phylink_pcs_ops and being
less reliant on the phy_interface_t passed to xpcs_probe (now renamed to
xpcs_create).

This patch series is partially tested (some code paths have been covered
on the NXP SJA1105 and some others with the help of Vee Khee Wong on
Intel Tiger Lake / stmmac) but further testing on 10G setups would be
appreciated, if possible.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>