userspace/wqueue: move exclusive access lock to mqueue inside

Change-Id: I885d5641bc81fedf698c241d4719cb3561700f17
Signed-off-by: Jiuzhu Dong <dongjiuzhu1@xiaomi.com>

libs/libc/wqueue/work_queue.c

@@ -78,7 +78,7 @@ static int work_qqueue(FAR struct usr_wqueue_s *wqueue,
 
   /* Get exclusive access to the work queue */
 
-  while (work_lock() < 0);
+  while (_SEM_WAIT(&wqueue->lock) < 0);
 
   /* Is there already pending work? */
 
@@ -104,7 +104,7 @@ static int work_qqueue(FAR struct usr_wqueue_s *wqueue,
   dq_addlast((FAR dq_entry_t *)work, &wqueue->q);
   kill(wqueue->pid, SIGWORK);   /* Wake up the worker thread */
 
-  work_unlock();
+  _SEM_POST(&wqueue->lock);
   return OK;
 }