fs/afs/vlocation: Remove deprecated create_singlethread_workqueue

The workqueue "afs_vlocation_update_worker" queues a single work item
&afs_vlocation_update and hence it doesn't require execution ordering.
Hence, alloc_workqueue has been used to replace the deprecated
create_singlethread_workqueue instance.

Since the workqueue is being used on a memory reclaim path, WQ_MEM_RECLAIM
flag has been set to ensure forward progress under memory pressure.

Since there are fixed number of work items, explicit concurrency
limit is unnecessary here.
Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>

fs/afs/vlocation.c

@@ -594,8 +594,8 @@ static void afs_vlocation_reaper(struct work_struct *work)
  */
 int __init afs_vlocation_update_init(void)
 {
-	afs_vlocation_update_worker =
-		create_singlethread_workqueue("kafs_vlupdated");
+	afs_vlocation_update_worker = alloc_workqueue("kafs_vlupdated",
+						      WQ_MEM_RECLAIM, 0);
 	return afs_vlocation_update_worker ? 0 : -ENOMEM;
 }