IB/mlx4/mad: Remove deprecated create_singlethread_workqueue

alloc_ordered_workqueue() with WQ_MEM_RECLAIM set, replaces
deprecated create_singlethread_workqueue(). This is the identity
conversion.

The workqueue "wq" queues work item &ctx->work and the workqueue "ud_wq"
queues work item &dm[i]->work.

Both the workqueues have been identity converted.

WQ_MEM_RECLAIM has been set to ensure forward progress under
memory pressure.
Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/mlx4/mad.c

@@ -2070,7 +2070,7 @@ static int mlx4_ib_alloc_demux_ctx(struct mlx4_ib_dev *dev,
 	}
 
 	snprintf(name, sizeof name, "mlx4_ibt%d", port);
-	ctx->wq = create_singlethread_workqueue(name);
+	ctx->wq = alloc_ordered_workqueue(name, WQ_MEM_RECLAIM);
 	if (!ctx->wq) {
 		pr_err("Failed to create tunnelling WQ for port %d\n", port);
 		ret = -ENOMEM;
@@ -2078,7 +2078,7 @@ static int mlx4_ib_alloc_demux_ctx(struct mlx4_ib_dev *dev,
 	}
 
 	snprintf(name, sizeof name, "mlx4_ibud%d", port);
-	ctx->ud_wq = create_singlethread_workqueue(name);
+	ctx->ud_wq = alloc_ordered_workqueue(name, WQ_MEM_RECLAIM);
 	if (!ctx->ud_wq) {
 		pr_err("Failed to create up/down WQ for port %d\n", port);
 		ret = -ENOMEM;