iommu/mediatek: Add a flag STD_AXI_MODE

Add a new flag STD_AXI_MODE which is prepared for infra and apu iommu
which use the standard axi mode. All the current SoC don't use this flag.

Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/20220503071427.2285-13-yong.wu@mediatek.com


Signed-off-by: Joerg Roedel <jroedel@suse.de>