sched: run_rebalance_domains: s/SCHED_IDLE/CPU_IDLE/

rebalance_domains(SCHED_IDLE) looks strange (typo), change it to CPU_IDLE.

the effect of this bug was slightly more agressive idle-balancing on
SMP than intended.
Signed-off-by: NOleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

kernel/sched.c

@@ -3106,7 +3106,7 @@ static void run_rebalance_domains(struct softirq_action *h)
 			if (need_resched())
 				break;
 
-			rebalance_domains(balance_cpu, SCHED_IDLE);
+			rebalance_domains(balance_cpu, CPU_IDLE);
 
 			rq = cpu_rq(balance_cpu);
 			if (time_after(this_rq->next_balance, rq->next_balance))