Add device tree files for Solidrun ClearFog Base board.
We also need to backport some improvements for Armada
388 MicroSoM.

The base model is a smaller version of ClearFog Pro without
the DSA switch, replacing it with a second copper gigabit
port, and only one PCIe socket.

Signed-off-by: Marko Ratkaj <marko.ratkaj@sartura.hr>