cpumask: alloc zeroed cpumask for static cpumask_var_ts

These are defined as static cpumask_var_t so if MAXSMP is not used,
they are cleared already.  Avoid surprises when MAXSMP is enabled.

Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
index 54b6de2..752e8c6 100644
--- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
+++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c
@@ -550,7 +550,7 @@
 		return -ENOMEM;
 	}
 	for_each_possible_cpu(i) {
-		if (!alloc_cpumask_var_node(
+		if (!zalloc_cpumask_var_node(
 			&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
 			GFP_KERNEL, cpu_to_node(i))) {