PM / devfreq: Fix governor_store()

Writing the currently set governor into sysfs currently
seems to fail.
Fix this by setting the return code to zero before
leaving governor_store().
Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>

drivers/devfreq/devfreq.c

@@ -795,8 +795,10 @@ static ssize_t governor_store(struct device *dev, struct device_attribute *attr,
 		ret = PTR_ERR(governor);
 		goto out;
 	}
-	if (df->governor == governor)
+	if (df->governor == governor) {
+		ret = 0;
 		goto out;
+	}
 
 	if (df->governor) {
 		ret = df->governor->event_handler(df, DEVFREQ_GOV_STOP, NULL);