iommu/vt-d: Fix misuse of iommu_domain_identity_map()

The iommu_domain_identity_map() helper takes start/end PFN as arguments.
Fix a misuse case where the start and end addresses are passed.

Fixes: e70b081c ("iommu/vt-d: Remove IOVA handling code from the non-dma_ops path")
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Cc: Tom Murphy <murphyt7@tcd.ie>
Link: https://lore.kernel.org/r/20200622231345.29722-7-baolu.lu@linux.intel.comSigned-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel/iommu.c

@@ -2701,7 +2701,9 @@ static int __init si_domain_init(int hw)
 				    end >> agaw_to_width(si_domain->agaw)))
 				continue;
 
-			ret = iommu_domain_identity_map(si_domain, start, end);
+			ret = iommu_domain_identity_map(si_domain,
+					mm_to_dma_pfn(start >> PAGE_SHIFT),
+					mm_to_dma_pfn(end >> PAGE_SHIFT));
 			if (ret)
 				return ret;
 		}