cpumask: cpu_coregroup_mask(): s390

Like cpu_coregroup_map, but returns a (const) pointer.

Compile-tested on s390 (defconfig).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c
index a947899..0601cd3 100644
--- a/arch/s390/kernel/topology.c
+++ b/arch/s390/kernel/topology.c
@@ -93,6 +93,11 @@
 	return mask;
 }
 
+const struct cpumask *cpu_coregroup_mask(unsigned int cpu)
+{
+	return &cpu_core_map[cpu];
+}
+
 static void add_cpus_to_core(struct tl_cpu *tl_cpu, struct core_info *core)
 {
 	unsigned int cpu;