make kernel_shutdown_prepare() static

kernel_shutdown_prepare() can now become static.

Signed-off-by: Adrian Bunk <[e-mail]>
Acked-by: Pavel Machek <[e-mail]>
Cc: "Rafael J. Wysocki" <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

include/linux/reboot.h

···
  * Architecture independent implemenations of sys_reboot commands.
  */
 
-extern void kernel_shutdown_prepare(enum system_states state);
-
 extern void kernel_restart(char *cmd);
 extern void kernel_halt(void);
 extern void kernel_power_off(void);

kernel/sys.c

···
 #endif
 }
 
-void kernel_shutdown_prepare(enum system_states state)
+static void kernel_shutdown_prepare(enum system_states state)
 {
 	blocking_notifier_call_chain(&reboot_notifier_list,
 		(state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL);