iommu/s390: Optimize IOMMU table walking

When invalidating existing table entries for unmap there is no need to
know the physical address beforehand so don't do an extra walk of the
IOMMU table to get it. Also when invalidating entries not finding an
entry indicates an invalid unmap and not a lack of memory we also don't
need to undo updates in this case. Implement this by splitting
s390_iommu_update_trans() in a variant for validating and one for
invalidating translations.

Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20221109142903.4080275-5-schnelle@linux.ibm.com


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