notifiers: sys: move reboot notifiers into reboot.h

It is not necessary to share the same notifier.h.

This patch already moves register_reboot_notifier() and
unregister_reboot_notifier() from kernel/notifier.c to kernel/sys.c.

[amwang@redhat.com: make allyesconfig succeed on ppc64]
Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: David Miller <davem@davemloft.net>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: WANG Cong <amwang@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/reboot.h b/include/linux/reboot.h
index 3005d5a..e0879a7 100644
--- a/include/linux/reboot.h
+++ b/include/linux/reboot.h
@@ -39,6 +39,11 @@
 
 #include <linux/notifier.h>
 
+#define SYS_DOWN	0x0001	/* Notify of system down */
+#define SYS_RESTART	SYS_DOWN
+#define SYS_HALT	0x0002	/* Notify of system halt */
+#define SYS_POWER_OFF	0x0003	/* Notify of system power off */
+
 extern int register_reboot_notifier(struct notifier_block *);
 extern int unregister_reboot_notifier(struct notifier_block *);