iommu/amd: Finish TLB flush in amd_iommu_unmap()

The function only sends the flush command to the IOMMU(s),
but does not wait for its completion when it returns. Fix
that.

Fixes: 601367d76bd1 ('x86/amd-iommu: Remove iommu_flush_domain function')
Cc: stable@vger.kernel.org # >= 2.6.33
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/amd_iommu.c

@@ -3048,6 +3048,7 @@ static size_t amd_iommu_unmap(struct iommu_domain *dom, unsigned long iova,
 	mutex_unlock(&domain->api_lock);
 
 	domain_flush_tlb_pde(domain);
+	domain_flush_complete(domain);
 
 	return unmap_size;
 }