iommu/vt-d: Remove unnecessary (void*) conversions

No need cast (void*) to (struct root_entry *).

Signed-off-by: Suhui <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Lu Baolu <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>

Author: Suhui

drivers/iommu/intel/iommu.c

@@ -1185,7 +1185,7 @@ static int iommu_alloc_root_entry(struct intel_iommu *iommu)
 {
 	struct root_entry *root;
 
-	root = (struct root_entry *)alloc_pgtable_page(iommu->node, GFP_ATOMIC);
+	root = alloc_pgtable_page(iommu->node, GFP_ATOMIC);
 	if (!root) {
 		pr_err("Allocating root entry for %s failed\n",
 			iommu->name);