Airoha EN8801SC PHY is a gigabit PHY used on Edgecore EAP111 so, include
the MTK driver with some cleanups.
Unfortunatelly, there is no specification sheet nor datasheet available
in order to demistify the magic PBUS writes and work on upstreaming
this driver.
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
