iommu/mediatek: Get the proper bankid for multi banks

We preassign some ports in a special bank via the new defined
banks_portmsk. Put it in the plat_data means it is not expected to be
adjusted dynamically.

If the iommu id in the iommu consumer's dtsi node is inside this
banks_portmsk, then we switch it to this special iommu bank, and
initialise the IOMMU bank HW.

Each bank has the independent pgtable(4GB iova range). Each bank
is a independent iommu domain/group. Currently we don't separate different
iova ranges inside a bank.

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/20220503071427.2285-33-yong.wu@mediatek.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>