iommu/vt-d: Remove deferred_attach_domain()

The function is now only a wrapper around find_domain(). Remove the
function and call find_domain() directly at the call-sites.

Fixes: 1ee0186b ("iommu/vt-d: Refactor find_domain() helper")
Cc: stable@vger.kernel.org # v5.5
Reviewed-by: NJerry Snitselaar <jsnitsel@redhat.com>
Acked-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>

drivers/iommu/intel-iommu.c

@@ -2539,11 +2539,6 @@ static void do_deferred_attach(struct device *dev)
 		intel_iommu_attach_device(domain, dev);
 }
 
-static struct dmar_domain *deferred_attach_domain(struct device *dev)
-{
-	return find_domain(dev);
-}
-
 static inline struct device_domain_info *
 dmar_search_domain_by_dev_info(int segment, int bus, int devfn)
 {
@@ -3643,7 +3638,7 @@ static dma_addr_t __intel_map_single(struct device *dev, phys_addr_t paddr,
 
 	BUG_ON(dir == DMA_NONE);
 
-	domain = deferred_attach_domain(dev);
+	domain = find_domain(dev);
 	if (!domain)
 		return DMA_MAPPING_ERROR;
 
@@ -3863,7 +3858,7 @@ static int intel_map_sg(struct device *dev, struct scatterlist *sglist, int nele
 	if (!iommu_need_mapping(dev))
 		return dma_direct_map_sg(dev, sglist, nelems, dir, attrs);
 
-	domain = deferred_attach_domain(dev);
+	domain = find_domain(dev);
 	if (!domain)
 		return 0;
 
@@ -3961,7 +3956,7 @@ bounce_map_single(struct device *dev, phys_addr_t paddr, size_t size,
 	if (unlikely(attach_deferred(dev)))
 		do_deferred_attach(dev);
 
-	domain = deferred_attach_domain(dev);
+	domain = find_domain(dev);
 
 	if (WARN_ON(dir == DMA_NONE || !domain))
 		return DMA_MAPPING_ERROR;