iommu/vt-d: Remove virtual command interface

Virtual command interface was introduced to allow using host PASIDs
inside VMs. It is unused and abandoned due to architectural change.

With this patch, we can safely remove this feature and the related helpers.

Link: https://lore.kernel.org/r/20230210230206.3160144-2-jacob.jun.pan@linux.intel.com


Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20230322200803.869130-2-jacob.jun.pan@linux.intel.com


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