perf_counter/x86: Always use NMI for performance-monitoring interrupt

Always use NMI for performance-monitoring interrupt as there could be
racy situations if we switch between irq and nmi mode frequently.

Signed-off-by: Yong Wang <yong.y.wang@intel.com>
LKML-Reference: <20090529052835.GA13657@ywang-moblin2.bj.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/apic/apic.c

@@ -1135,7 +1135,7 @@ void __cpuinit setup_local_APIC(void)
 		apic_write(APIC_ESR, 0);
 	}
 #endif
-	perf_counters_lapic_init(0);
+	perf_counters_lapic_init();
 
 	preempt_disable();