iommu: Remove guest pasid related interfaces and definitions

The guest pasid related uapi interfaces and definitions are not referenced
anywhere in the tree. We've also reached a consensus to replace them with
a new iommufd design. Remove them to avoid dead code.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20220216025249.3459465-3-baolu.lu@linux.intel.com


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