clockevents: Allow build w/o run-tine usage for migration purposes

Migration aid to allow preparatory patches which introduce not yet
used parts of clock events code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>

diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 41dd310..822beeb 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -194,6 +194,7 @@
 	local_irq_restore(flags);
 }
 
+#ifdef CONFIG_GENERIC_CLOCKEVENTS
 /**
  * clockevents_notify - notification about relevant events
  */
@@ -222,4 +223,4 @@
 	spin_unlock(&clockevents_lock);
 }
 EXPORT_SYMBOL_GPL(clockevents_notify);
-
+#endif