workqueue: make delayed_work_timer_fn() static

delayed_work_timer_fn() is a timer function, make it static.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

include/linux/timer.h

@@ -124,8 +124,6 @@ static inline void timer_stats_timer_clear_start_info(struct timer_list *timer)
 }
 #endif
 
-extern void delayed_work_timer_fn(unsigned long __data);
-
 /**
  * add_timer - start a timer
  * @timer: the timer to be added

kernel/workqueue.c

@@ -175,7 +175,7 @@ int queue_work(struct workqueue_struct *wq, struct work_struct *work)
 }
 EXPORT_SYMBOL_GPL(queue_work);
 
-void delayed_work_timer_fn(unsigned long __data)
+static void delayed_work_timer_fn(unsigned long __data)
 {
 	struct delayed_work *dwork = (struct delayed_work *)__data;
 	struct cpu_workqueue_struct *cwq = get_wq_data(&dwork->work);