sched/wait: Make the signal_pending() checks consistent

sched/wait: Make the signal_pending() checks consistent

There's two patterns to check signals in the __wait_event*() macros:

  if (!signal_pending(current)) {
	schedule();
	continue;
  }
  ret = -ERESTARTSYS;
  break;

And the more natural:

  if (signal_pending(current)) {
	ret = -ERESTARTSYS;
	break;
  }
  schedule();

Change them all into the latter form.

Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131002092527.956416254@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>