ARM: EXYNOS: replace cpumask by the corresponding macro

A trivial patch to replace for_each_cpu(cpu_id, cpu_online_mask) by
the corresponding macro.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/mach-exynos/cpuidle.c

@@ -206,7 +206,7 @@ static int __init exynos4_init_cpuidle(void)
 		return ret;
 	}
 
-	for_each_cpu(cpu_id, cpu_online_mask) {
+	for_each_online_cpu(cpu_id) {
 		device = &per_cpu(exynos4_cpuidle_device, cpu_id);
 		device->cpu = cpu_id;