iommu/vt-d: Lift the __pa to domain_setup_first_level/intel_svm_set_dev_pasid()

iommu/vt-d: Lift the __pa to domain_setup_first_level/intel_svm_set_dev_pasid()

Pass the phys_addr_t down through the call chain from the top instead of
passing a pgd_t * KVA. This moves the __pa() into
domain_setup_first_level() which is the first function to obtain the pgd
from the IOMMU page table in this call chain.

The SVA flow is also adjusted to get the pa of the mm->pgd.

iommput will move the __pa() into iommupt code, it never shares the KVA of
the page table with the driver.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/1-v3-dbbe6f7e7ae3+124ffe-vtd_prep_jgg@nvidia.com
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20250714045028.958850-4-baolu.lu@linux.intel.com
Signed-off-by: Will Deacon <will@kernel.org>