sched/fair: Push down check for high priority class task into idle_balance()

We close idle_exit_fair() bracket in case of we've pulled something or we've received
task of high priority class.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Link: http://lkml.kernel.org/r/1394098315.19290.10.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>

kernel/sched/idle_task.c

@@ -29,7 +29,6 @@ pick_next_task_idle(struct rq *rq, struct task_struct *prev)
 	put_prev_task(rq, prev);
 
 	schedstat_inc(rq, sched_goidle);
-	idle_enter_fair(rq);
 	return rq->idle;
 }