x86: fix more deprecated cpu function usage.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/arch/x86/kernel/apic/x2apic_cluster.c b/arch/x86/kernel/apic/x2apic_cluster.c
index d9d0bd2..ab3219b 100644
--- a/arch/x86/kernel/apic/x2apic_cluster.c
+++ b/arch/x86/kernel/apic/x2apic_cluster.c
@@ -171,8 +171,8 @@
 		for_each_online_cpu(cpu) {
 			if (x2apic_cluster(this_cpu) != x2apic_cluster(cpu))
 				continue;
-			__cpu_clear(this_cpu, per_cpu(cpus_in_cluster, cpu));
-			__cpu_clear(cpu, per_cpu(cpus_in_cluster, this_cpu));
+			cpumask_clear_cpu(this_cpu, per_cpu(cpus_in_cluster, cpu));
+			cpumask_clear_cpu(cpu, per_cpu(cpus_in_cluster, this_cpu));
 		}
 		free_cpumask_var(per_cpu(cpus_in_cluster, this_cpu));
 		free_cpumask_var(per_cpu(ipi_mask, this_cpu));