net: ethernet: mtk_eth_soc: support 36-bit DMA addressing on MT7988

Systems having 4 GiB of RAM and more require DMA addressing beyond the
current 32-bit limit. Starting from MT7988 the hardware now supports
36-bit DMA addressing, let's use that new capability in the driver to
avoid running into swiotlb on systems with 4 GiB of RAM or more.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Link: https://lore.kernel.org/r/95b919c98876c9e49761e44662e7c937479eecb8.1692721443.git.daniel@makrotopia.org


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