arm64: dts: mediatek: mt8390-genio-700-evk: Enable ethernet

Enable ethernet on the Genio 700 EVK board. It has been tested to work
with speeds up to 1000Mbps.

[Cleaned up to pass dtbs_check, follow DTS style guidelines, and split
between mt8188 and genio700 commits, and addressed further feedback from
the mailing list]

Signed-off-by: Jianguo Zhang <jianguo.zhang@mediatek.com>
Signed-off-by: Macpaul Lin <macpaul.lin@mediatek.com>
Signed-off-by: Hsuan-Yu Lin <shane.lin@canonical.com>
Signed-off-by: Pablo Sun <pablo.sun@mediatek.com>
Signed-off-by: fanyi zhang <fanyi.zhang@mediatek.com>
Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20241018-genio700-eth-v2-2-f3c73b85507b@collabora.com


Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>