iommu: Remove ops.pgsize_bitmap from drivers that don't use it

iommu: Remove ops.pgsize_bitmap from drivers that don't use it

These drivers all set the domain->pgsize_bitmap in their
domain_alloc_paging() functions, so the ops value is never used. Delete
it.

Reviewed-by: Sven Peter <sven@svenpeter.dev> # for Apple DART
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Tomasz Jeznach <tjeznach@rivosinc.com> # for RISC-V
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Link: https://lore.kernel.org/r/3-v2-68a2e1ba507c+1fb-iommu_rm_ops_pgsize_jgg@nvidia.com
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>