PM / devfreq: remove double put_device

When device_register() returns with error, it has already
done put_device() on the input device pointer.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>

drivers/devfreq/devfreq.c

@@ -564,7 +564,6 @@ struct devfreq *devfreq_add_device(struct device *dev,
 	dev_set_name(&devfreq->dev, "%s", dev_name(dev));
 	err = device_register(&devfreq->dev);
 	if (err) {
-		put_device(&devfreq->dev);
 		mutex_unlock(&devfreq->lock);
 		goto err_out;
 	}