Merge branch 'prepare-dwmac-meson8b-for-G12A-specific-initialization'

Martin Blumenstingl says:

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prepare dwmac-meson8b for G12A specific initialization

Some users are reporting that RGMII (and sometimes also RMII) Ethernet
is not working for them on G12A/G12B/SM1 boards. Upon closer inspection
of the vendor code for these SoCs new register bits are found.

It's not clear yet how these registers work. Add a new compatible string
as the first preparation step to improve Ethernet support on these SoCs.
====================

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