iommu/vt-d: Simplify check in identity_mapping()

The function only has one call-site and there it is never called with
dummy or deferred devices. Simplify the check in the function to
account for that.

Fixes: 1ee0186 ("iommu/vt-d: Refactor find_domain() helper")
Cc: [email protected] # v5.5
Reviewed-by: Jerry Snitselaar <[email protected]>
Acked-by: Lu Baolu <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>

drivers/iommu/intel-iommu.c

@@ -2916,7 +2916,7 @@ static int identity_mapping(struct device *dev)
 	struct device_domain_info *info;
 
 	info = dev->archdata.iommu;
-	if (info && info != DUMMY_DEVICE_DOMAIN_INFO && info != DEFER_DEVICE_DOMAIN_INFO)
+	if (info)
 		return (info->domain == si_domain);
 
 	return 0;