unexport pm_power_off_prepare

This patch removes the unused EXPORT_SYMBOL(pm_power_off_prepare).
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/sys.c

@@ -105,7 +105,6 @@ EXPORT_SYMBOL(cad_pid);
  */
 
 void (*pm_power_off_prepare)(void);
-EXPORT_SYMBOL(pm_power_off_prepare);
 
 /*
  *	Notifier list for kernel code which wants to be called