iommu/vt-d: Fix sysfs leak in alloc_iommu()

iommu_device_sysfs_add() is called before, so is has to be cleaned on subsequent
errors.

Fixes: 39ab955 ("iommu: Add sysfs bindings for struct iommu_device")
Cc: stable@vger.kernel.org # 4.11.x
Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Acked-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/17411490.HIIP88n32C@mobilepool36.emlix.com
Link: https://lore.kernel.org/r/20210525070802.361755-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel/dmar.c

@@ -1142,14 +1142,16 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd)
 
 		err = iommu_device_register(&iommu->iommu, &intel_iommu_ops, NULL);
 		if (err)
-			goto err_unmap;
+			goto err_sysfs;
 	}
 
 	drhd->iommu = iommu;
 	iommu->drhd = drhd;
 
 	return 0;
 
+err_sysfs:
+	iommu_device_sysfs_remove(&iommu->iommu);
 err_unmap:
 	unmap_iommu(iommu);
 error_free_seq_id: