x86: Fix sparse non-ANSI function warnings in smpboot.c

Fix sparse warning for non-ANSI function declaration:

  arch/x86/kernel/smpboot.c💯30: warning: non-ANSI function declaration of function 'cpu_hotplug_driver_lock'
  arch/x86/kernel/smpboot.c:105:32: warning: non-ANSI function declaration of function 'cpu_hotplug_driver_unlock'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
LKML-Reference: <20110108195914.95d366ea.randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/smpboot.c

@@ -97,12 +97,12 @@ static DEFINE_PER_CPU(struct task_struct *, idle_thread_array);
  */
 static DEFINE_MUTEX(x86_cpu_hotplug_driver_mutex);
 
-void cpu_hotplug_driver_lock()
+void cpu_hotplug_driver_lock(void)
 {
         mutex_lock(&x86_cpu_hotplug_driver_mutex);
 }
 
-void cpu_hotplug_driver_unlock()
+void cpu_hotplug_driver_unlock(void)
 {
         mutex_unlock(&x86_cpu_hotplug_driver_mutex);
 }