alarmtimer: Drop device refcount after rtc_open()

class_find_device() takes a refcount on the rtc device. rtc_open()
takes another one, so we can drop it after the rtc_open() call.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index e5db9b0..c6027fe 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -675,8 +675,14 @@
 	/* Find an rtc device and init the rtc_timer */
 	dev = class_find_device(rtc_class, NULL, &str, has_wakealarm);
 	/* If we have a device then str is valid. See has_wakealarm() */
-	if (dev)
+	if (dev) {
 		rtcdev = rtc_class_open(str);
+		/*
+		 * Drop the reference we got in class_find_device,
+		 * rtc_open takes its own.
+		 */
+		put_device(dev);
+	}
 	if (!rtcdev) {
 		printk(KERN_WARNING "No RTC device found, ALARM timers will"
 			" not wake from suspend");