clockevents: export clockevents_config_and_register for module use

clockevents_config_and_register is a handy helper for clockevent
drivers, some of which might support module build, so export the symbol.
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NOlof Johansson <olof@lixom.net>

kernel/time/clockevents.c

@@ -339,6 +339,7 @@ void clockevents_config_and_register(struct clock_event_device *dev,
 	clockevents_config(dev, freq);
 	clockevents_register_device(dev);
 }
+EXPORT_SYMBOL_GPL(clockevents_config_and_register);
 
 /**
  * clockevents_update_freq - Update frequency and reprogram a clock event device.