drivers/phy: Add Marvell SerDes / PHY drivers used on Armada 7K/8K

drivers/phy: Add Marvell SerDes / PHY drivers used on Armada 7K/8K

This version is based on the Marvell U-Boot version with this patch
applied as latest patch:

Git ID 7f408573: "fix: comphy: cp110: add comphy initialization for usb
device mode" from 2016-07-05.

Signed-off-by: Stefan Roese <[email protected]>
Cc: Nadav Haklai <[email protected]>
Cc: Neta Zur Hershkovits <[email protected]>
Cc: Kostya Porotchkin <[email protected]>
Cc: Omri Itach <[email protected]>
Cc: Igal Liberman <[email protected]>
Cc: Haim Boot <[email protected]>
Cc: Hanna Hawa <[email protected]>