alarmtimer: Export symbols of alarmtimer_get_rtcdev

Export symbol of alarmtimer_get_rtcdev so that it is used by
any driver when built as module like,
drivers/staging/android/alarm-dev.c.

CC: John Stultz <john.stultz@linaro.org>
CC: Marcus Gelderie <redmnic@gmail.com>
Signed-off-by: NPramod Gurav <pramod.gurav.etc@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

kernel/time/alarmtimer.c

@@ -71,7 +71,7 @@ struct rtc_device *alarmtimer_get_rtcdev(void)
 
 	return ret;
 }
-
+EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev);
 
 static int alarmtimer_rtc_add_device(struct device *dev,
 				struct class_interface *class_intf)