x86: simplify idle selection

default_idle is selected in cpu_idle(), when no other idle routine is
selected. Select it in select_idle_routine() when mwait is not
selected.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index f8476df..ee4ab46 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -168,24 +168,19 @@
 	while (1) {
 		tick_nohz_stop_sched_tick();
 		while (!need_resched()) {
-			void (*idle)(void);
 
 			check_pgt_cache();
 			rmb();
-			idle = pm_idle;
 
 			if (rcu_pending(cpu))
 				rcu_check_callbacks(cpu, 0);
 
-			if (!idle)
-				idle = default_idle;
-
 			if (cpu_is_offline(cpu))
 				play_dead();
 
 			local_irq_disable();
 			__get_cpu_var(irq_stat).idle_timestamp = jiffies;
-			idle();
+			pm_idle();
 		}
 		tick_nohz_restart_sched_tick();
 		preempt_enable_no_resched();