r8169: sync support for RTL8401 with vendor driver

So far RTL8401 was treated like a RTL8101e, means we relied on the BIOS
to configure MAC and PHY properly. Make RTL8401 a separate chip version
and copy MAC / PHY config from r8101 vendor driver.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>