mt76: add support for overriding the device used for DMA mapping

[ Upstream commit d1ddc536 ]

WED support requires using non-coherent DMA, whereas the PCI device might
be configured for coherent DMA.
The WED driver will take care of changing the PCI HIF coherent IO setting
on attach.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Stable-dep-of: 31762059 ("wifi: mt76: mt7603: improve stuck beacon handling")
Signed-off-by: Sasha Levin <sashal@kernel.org>