dt-bindings: net: Document moca PHY interface

MoCA (Multimedia over Coaxial) is used by the internal GENET/MOCA cores
and will be needed in order to convert GENET to YAML in subsequent
changes.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20211206180049.2086907-4-f.fainelli@gmail.comSigned-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/net/ethernet-controller.yaml

@@ -69,6 +69,7 @@ properties:
       - rev-mii
       - rmii
       - rev-rmii
+      - moca
 
       # RX and TX delays are added by the MAC when required
       - rgmii