From: Miklos Szeredi <miklos@szeredi.hu>

  LD      .tmp_vmlinux1
kernel/built-in.o(.text+0x148e1): In function `sys_reboot':
kernel/sys.c:535: undefined reference to `pm_power_off'

On uml machine_halt() just calls machine_power_off() so it's safe to leave
pm_power_off as NULL.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 arch/um/kernel/reboot.c |    2 ++
 1 files changed, 2 insertions(+)

diff -puN arch/um/kernel/reboot.c~dont-attempt-to-power-off-if-power-off-is-not-implemented-uml-fix arch/um/kernel/reboot.c
--- devel/arch/um/kernel/reboot.c~dont-attempt-to-power-off-if-power-off-is-not-implemented-uml-fix	2005-12-12 11:23:01.000000000 -0800
+++ devel-akpm/arch/um/kernel/reboot.c	2005-12-12 11:23:01.000000000 -0800
@@ -12,6 +12,8 @@
 #include "mode.h"
 #include "choose-mode.h"
 
+void (*pm_power_off)(void);
+
 #ifdef CONFIG_SMP
 static void kill_idlers(int me)
 {
_