workqueue: gut system_nrt[_freezable]_wq()

Now that all workqueues are non-reentrant, system[_freezable]_wq() are
equivalent to system_nrt[_freezable]_wq().  Replace the latter with
wrappers around system[_freezable]_wq().  The wrapping goes through
inline functions so that __deprecated can be added easily.

Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 5f13a9a..85bd340 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -274,14 +274,10 @@
 EXPORT_SYMBOL_GPL(system_highpri_wq);
 struct workqueue_struct *system_long_wq __read_mostly;
 EXPORT_SYMBOL_GPL(system_long_wq);
-struct workqueue_struct *system_nrt_wq __read_mostly;
-EXPORT_SYMBOL_GPL(system_nrt_wq);
 struct workqueue_struct *system_unbound_wq __read_mostly;
 EXPORT_SYMBOL_GPL(system_unbound_wq);
 struct workqueue_struct *system_freezable_wq __read_mostly;
 EXPORT_SYMBOL_GPL(system_freezable_wq);
-struct workqueue_struct *system_nrt_freezable_wq __read_mostly;
-EXPORT_SYMBOL_GPL(system_nrt_freezable_wq);
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/workqueue.h>
@@ -3838,16 +3834,12 @@
 	system_wq = alloc_workqueue("events", 0, 0);
 	system_highpri_wq = alloc_workqueue("events_highpri", WQ_HIGHPRI, 0);
 	system_long_wq = alloc_workqueue("events_long", 0, 0);
-	system_nrt_wq = alloc_workqueue("events_nrt", WQ_NON_REENTRANT, 0);
 	system_unbound_wq = alloc_workqueue("events_unbound", WQ_UNBOUND,
 					    WQ_UNBOUND_MAX_ACTIVE);
 	system_freezable_wq = alloc_workqueue("events_freezable",
 					      WQ_FREEZABLE, 0);
-	system_nrt_freezable_wq = alloc_workqueue("events_nrt_freezable",
-			WQ_NON_REENTRANT | WQ_FREEZABLE, 0);
 	BUG_ON(!system_wq || !system_highpri_wq || !system_long_wq ||
-	       !system_nrt_wq || !system_unbound_wq || !system_freezable_wq ||
-	       !system_nrt_freezable_wq);
+	       !system_unbound_wq || !system_freezable_wq);
 	return 0;
 }
 early_initcall(init_workqueues);