iommu/vt-d: Remove dead code in device_notifier

This code only runs when action == BUS_NOTIFY_REMOVED_DEVICE,
so it can't be BUS_NOTIFY_DEL_DEVICE.
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel-iommu.c

@@ -4029,14 +4029,6 @@ static int device_notifier(struct notifier_block *nb,
 	if (action != BUS_NOTIFY_REMOVED_DEVICE)
 		return 0;
 
-	/*
-	 * If the device is still attached to a device driver we can't
-	 * tear down the domain yet as DMA mappings may still be in use.
-	 * Wait for the BUS_NOTIFY_UNBOUND_DRIVER event to do that.
-	 */
-	if (action == BUS_NOTIFY_DEL_DEVICE && dev->driver != NULL)
-		return 0;
-
 	domain = find_domain(dev);
 	if (!domain)
 		return 0;