lockup detector: Compile fixes from removing the old x86 nmi watchdog

My patch that removed the old x86 nmi watchdog broke other
arches.  This change reverts a piece of that patch and puts the
change in the correct spot.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: fweisbec@gmail.com
Cc: yinghai@kernel.org
LKML-Reference: <1291068437-5331-2-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

include/linux/nmi.h

@@ -16,7 +16,8 @@
  */
 #ifdef ARCH_HAS_NMI_WATCHDOG
 #include <asm/nmi.h>
-#endif
+extern void touch_nmi_watchdog(void);
+#else
 #ifndef CONFIG_HARDLOCKUP_DETECTOR
 static inline void touch_nmi_watchdog(void)
 {
@@ -25,6 +26,7 @@ static inline void touch_nmi_watchdog(void)
 #else
 extern void touch_nmi_watchdog(void);
 #endif
+#endif
 
 /*
  * Create trigger_all_cpu_backtrace() out of the arch-provided