mlxsw: core: Remove deprecated create_workqueue

alloc_workqueue replaces deprecated create_workqueue().

A dedicated workqueue has been used since the workqueue
mlxsw_wq is used for FDB notif. processing with workitems that are
involved in normal device operation && because it's a network device
which can be depended upon during memory reclaim.

Workitems &trans->timeout_dw and &mlxsw_sp->fdb_notify.dw,
map to mlxsw_sp_fdb_notify_work (processes FDB notifications from the
underlying device and resolves the netdev to which the entry points to
and notifies the bridge using the switchdev notifier) and
mlxsw_emad_trans_timeout_work (provides async EMAD register access)
respectively. They require forward progress under memory pressure and
hence, WQ_MEM_RECLAIM has been set.

Since there are only a fixed number of work items, explicit concurrency
limit is unnecessary here.
Signed-off-by: NBhaktipriya Shridhar <bhaktipriya96@gmail.com>
Tested-by: NIdo Schimmel <idosch@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/core.c

@@ -1736,7 +1736,7 @@ static int __init mlxsw_core_module_init(void)
 {
 	int err;
 
-	mlxsw_wq = create_workqueue(mlxsw_core_driver_name);
+	mlxsw_wq = alloc_workqueue(mlxsw_core_driver_name, WQ_MEM_RECLAIM, 0);
 	if (!mlxsw_wq)
 		return -ENOMEM;
 	mlxsw_core_dbg_root = debugfs_create_dir(mlxsw_core_driver_name, NULL);