wifi: mt76: add flexible polling wait-interval support

The default waiting unit is 10ms and the value is too much for
data path related control. Provide a new API mt76_poll_msec_tick()
to support different cases, such as 1ms polling waiting kick.

Reviewed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Deren Wu <deren.wu@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>