powerpc/smp: Make some symbols static

The sparse tool complains as follows:

arch/powerpc/kernel/smp.c:86:1: warning:
 symbol '__pcpu_scope_cpu_coregroup_map' was not declared. Should it be static?
arch/powerpc/kernel/smp.c:125:1: warning:
 symbol '__pcpu_scope_thread_group_l1_cache_map' was not declared. Should it be static?
arch/powerpc/kernel/smp.c:132:1: warning:
 symbol '__pcpu_scope_thread_group_l2_cache_map' was not declared. Should it be static?

These symbols are not used outside of smp.c, so this
commit marks them static.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210407125903.4139663-1-yukuai3@huawei.com

arch/powerpc/kernel/smp.c

@@ -83,7 +83,7 @@ DEFINE_PER_CPU(cpumask_var_t, cpu_sibling_map);
 DEFINE_PER_CPU(cpumask_var_t, cpu_smallcore_map);
 DEFINE_PER_CPU(cpumask_var_t, cpu_l2_cache_map);
 DEFINE_PER_CPU(cpumask_var_t, cpu_core_map);
-DEFINE_PER_CPU(cpumask_var_t, cpu_coregroup_map);
+static DEFINE_PER_CPU(cpumask_var_t, cpu_coregroup_map);
 
 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
 EXPORT_PER_CPU_SYMBOL(cpu_l2_cache_map);
@@ -122,14 +122,14 @@ static struct thread_groups_list tgl[NR_CPUS] __initdata;
  * On big-cores system, thread_group_l1_cache_map for each CPU corresponds to
  * the set its siblings that share the L1-cache.
  */
-DEFINE_PER_CPU(cpumask_var_t, thread_group_l1_cache_map);
+static DEFINE_PER_CPU(cpumask_var_t, thread_group_l1_cache_map);
 
 /*
  * On some big-cores system, thread_group_l2_cache_map for each CPU
  * corresponds to the set its siblings within the core that share the
  * L2-cache.
  */
-DEFINE_PER_CPU(cpumask_var_t, thread_group_l2_cache_map);
+static DEFINE_PER_CPU(cpumask_var_t, thread_group_l2_cache_map);
 
 /* SMP operations for this machine */
 struct smp_ops_t *smp_ops;