RDS: IB: Remove deprecated create_workqueue

alloc_workqueue replaces deprecated create_workqueue().

Since the driver is infiniband which can be used as block device and the
workqueue seems involved in regular operation of the device, so a
dedicated workqueue has been used  with WQ_MEM_RECLAIM set to guarantee
forward progress under memory pressure.
Since there are only a fixed number of work items, explicit concurrency
limit is unnecessary here.
Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/rds/ib_rdma.c

@@ -618,7 +618,7 @@ struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_ibdev,
 
 int rds_ib_mr_init(void)
 {
-	rds_ib_mr_wq = create_workqueue("rds_mr_flushd");
+	rds_ib_mr_wq = alloc_workqueue("rds_mr_flushd", WQ_MEM_RECLAIM, 0);
 	if (!rds_ib_mr_wq)
 		return -ENOMEM;
 	return 0;