net: ethernet: mediatek: move mt7623 settings out off the mt7530

Moving mt7623 logic out off mt7530, is required to make hardware setting
consistent after we introduce phylink to mtk driver.

Fixes: b8fc9f30

 ("net: ethernet: mediatek: Add basic PHYLINK support")
Reviewed-by: Sean Wang <sean.wang@mediatek.com>
Tested-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: René van Dorst <opensource@vdorst.com>
Signed-off-by: David S. Miller <davem@davemloft.net>