iommu/vt-d: Don't return error when device gets right domain

If a device gets a right domain in add_device ops, it shouldn't
return error.

Fixes: 942067f ("iommu/vt-d: Identify default domains replaced with private")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel-iommu.c

@@ -5388,10 +5388,7 @@ static int intel_iommu_add_device(struct device *dev)
 				domain_add_dev_info(si_domain, dev);
 				dev_info(dev,
 					 "Device uses a private identity domain.\n");
-				return 0;
 			}
-
-			return -ENODEV;
 		}
 	} else {
 		if (device_def_domain_type(dev) == IOMMU_DOMAIN_DMA) {
@@ -5406,10 +5403,7 @@ static int intel_iommu_add_device(struct device *dev)
 
 				dev_info(dev,
 					 "Device uses a private dma domain.\n");
-				return 0;
 			}
-
-			return -ENODEV;
 		}
 	}