arm: dts: mt7623: add gmacs to mt7623.dtsi

There are two gigabit MACs on the MT7623AI and MT7623NI SoCs. Add them to
mt7623.dtsi and adjust the DTs that call mt7623.dtsi.

Now that there are labels for the MACs, remove them from under &eth on the
DTs that call mt7623.dtsi. Remove the unnecessary mdio label from Bananapi
BPI-R2.

Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Link: https://lore.kernel.org/r/20230210182505.24597-2-arinc.unal@arinc9.com


Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>