iommu/vt-d: Simplify io/tlb flushing in intel_iommu_unmap

We don't need to do an expensive search for domain-ids
anymore, as we keep track of per-iommu domain-ids.

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

diff --cc drivers/iommu/intel-iommu.c
Simple merge