iommu/amd: Make use of domain_alloc and domain_free

Implement the new iommu-ops function pointers and remove the
obsolete domain_init and domain_destroy functions.

Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --cc drivers/iommu/amd_iommu.c
Simple merge

diff --cc drivers/iommu/amd_iommu_types.h
Simple merge