net: dsa: tag_mtk: assign per-port queues

Keeps traffic sent to the switch within link speed limits

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20221116080734.44013-6-nbd@nbd.name


Signed-off-by: Jakub Kicinski <kuba@kernel.org>