sched/wait: Collapse __wait_event_interruptible()

Reduce macro complexity by using the new ___wait_event() helper.
No change in behaviour, identical generated code.

Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131002092528.396949919@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

include/linux/wait.h

@@ -277,21 +277,8 @@ do {									\
 })
 
 #define __wait_event_interruptible(wq, condition, ret)			\
-do {									\
+	___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, ret,	\
-	DEFINE_WAIT(__wait);						\
+		      schedule())
-									\
-	for (;;) {							\
-		prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE);	\
-		if (condition)						\
-			break;						\
-		if (signal_pending(current)) {				\
-			ret = -ERESTARTSYS;				\
-			break;						\
-		}							\
-		schedule();						\
-	}								\
-	finish_wait(&wq, &__wait);					\
-} while (0)
 
 /**
  * wait_event_interruptible - sleep until a condition gets true