x86: arch_register_cpu() section fix

fix this on i386 allnoconfig:

 WARNING: vmlinux.o(.text+0x6f2e): Section mismatch: reference to .init.text:register_cpu (between 'arch_register_cpu' and 'text_poke')
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/topology.c

@@ -33,7 +33,7 @@
 
 static struct i386_cpu cpu_devices[NR_CPUS];
 
-int arch_register_cpu(int num)
+int __cpuinit arch_register_cpu(int num)
 {
 	/*
 	 * CPU0 cannot be offlined due to several
@@ -53,7 +53,8 @@ int arch_register_cpu(int num)
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
-void arch_unregister_cpu(int num) {
+void arch_unregister_cpu(int num)
+{
 	return unregister_cpu(&cpu_devices[num].cpu);
 }
 EXPORT_SYMBOL(arch_register_cpu);