iommu/amd: Introduce iommu_v1_map_page and iommu_v1_unmap_page

These implement map and unmap for AMD IOMMU v1 pagetable, which
will be used by the IO pagetable framework.

Also clean up unused extern function declarations.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Link: https://lore.kernel.org/r/20201215073705.123786-13-suravee.suthikulpanit@amd.com


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