wifi: mt76: use GFP_DMA32 for page_pool buffer allocation

wifi: mt76: use GFP_DMA32 for page_pool buffer allocation

Set GFP_DMA32 flag for page_pool buffers allocation since the hw relies
on 32-bit DMA addresses for WED offloading.

Tested-by: Daniel Pawlik <pawlik.dan@gmail.com>
Tested-by: Matteo Croce <teknoraver@meta.com>
Signed-off-by: Peter Chiu <chui-hao.chiu@mediatek.com>
Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Link: https://patch.msgid.link/20251008-wed-fixes-v1-2-8f7678583385@kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>