Import pending series introducing support for standalone PCS drivers.
This has previously already been used by the airoha target, and is
also the base for the closer-to-upstream patches for MediaTek MT7988
10G SerDes support.
In order to not having to diverge from upstream also backport series
for standardized handling for PHY and PCS SerDes pair polarity.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
18cbd83a14