iommu: Use Functions to set default domain type in iommu_set_def_domain_type()

There are functions now to set the default domain type which
take care of updating other necessary state. Don't open-code
it in iommu_set_def_domain_type() and use those functions
instead.
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/iommu.c

@@ -178,9 +178,11 @@ static int __init iommu_set_def_domain_type(char *str)
 	if (ret)
 		return ret;
 
-	iommu_set_cmd_line_dma_api();
+	if (pt)
+		iommu_set_default_passthrough(true);
+	else
+		iommu_set_default_translated(true);
 
-	iommu_def_domain_type = pt ? IOMMU_DOMAIN_IDENTITY : IOMMU_DOMAIN_DMA;
 	return 0;
 }
 early_param("iommu.passthrough", iommu_set_def_domain_type);