iommu/arm-smmu-v3: Implement the unmap_pages() IOMMU driver callback

Implement the unmap_pages() callback for ARM SMMUV3 driver to allow calls
from iommu_unmap to unmap multiple pages of the same size in one call.
Also remove the unmap() callback for the ARM SMMUV3 driver as it will
no longer be used.

Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/1627697831-158822-2-git-send-email-chenxiang66@hisilicon.com


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