workqueue: fix the comments of nr_idle

Since the worker rebinding behavior was refactored, there is
no idle worker off the idle_list now. The comment is outdated
and can be just removed.

It also groups nr_workers and nr_idle together.
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

kernel/workqueue.c

@@ -153,10 +153,9 @@ struct worker_pool {
 	unsigned long		watchdog_ts;	/* L: watchdog timestamp */
 
 	struct list_head	worklist;	/* L: list of pending works */
-	int			nr_workers;	/* L: total number of workers */
 
-	/* nr_idle includes the ones off idle_list for rebinding */
-	int			nr_idle;	/* L: currently idle ones */
+	int			nr_workers;	/* L: total number of workers */
+	int			nr_idle;	/* L: currently idle workers */
 
 	struct list_head	idle_list;	/* X: list of idle workers */
 	struct timer_list	idle_timer;	/* L: worker idle timeout */