sched: do_wait_for_common: use signal_pending_state()

Change do_wait_for_common() to use signal_pending_state() instead of open
coding.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/sched.c

@@ -4599,10 +4599,7 @@ do_wait_for_common(struct completion *x, long timeout, int state)
 		wait.flags |= WQ_FLAG_EXCLUSIVE;
 		__add_wait_queue_tail(&x->wait, &wait);
 		do {
-			if ((state == TASK_INTERRUPTIBLE &&
-			     signal_pending(current)) ||
-			    (state == TASK_KILLABLE &&
-			     fatal_signal_pending(current))) {
+			if (signal_pending_state(state, current)) {
 				timeout = -ERESTARTSYS;
 				break;
 			}