iommu/vt-d: Check correct capability for sagaw determination

Check 5-level paging capability for 57 bits address width instead of
checking 1GB large page capability.

Fixes: 53fc7ad6 ("iommu/vt-d: Correctly calculate sagaw value of IOMMU")
Cc: stable@vger.kernel.org
Reported-by: Raghunathan Srinivasan <raghunathan.srinivasan@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Raghunathan Srinivasan <raghunathan.srinivasan@intel.com>
Link: https://lore.kernel.org/r/20220916071212.2223869-2-yi.l.liu@intel.com


Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>