PM / devfreq: Replace devfreq->dev.parent as dev in devfreq_add_device

In devfreq_add_device, replace devfreq->dev.parent
as dev to keep code simple.
Signed-off-by: pierre Kuo <vichy.kuo@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

drivers/devfreq/devfreq.c

@@ -893,13 +893,13 @@ struct devfreq *devfreq_add_device(struct device *dev,
 		goto err_devfreq;
 
 	devfreq->nb_min.notifier_call = qos_min_notifier_call;
-	err = dev_pm_qos_add_notifier(devfreq->dev.parent, &devfreq->nb_min,
+	err = dev_pm_qos_add_notifier(dev, &devfreq->nb_min,
 				      DEV_PM_QOS_MIN_FREQUENCY);
 	if (err)
 		goto err_devfreq;
 
 	devfreq->nb_max.notifier_call = qos_max_notifier_call;
-	err = dev_pm_qos_add_notifier(devfreq->dev.parent, &devfreq->nb_max,
+	err = dev_pm_qos_add_notifier(dev, &devfreq->nb_max,
 				      DEV_PM_QOS_MAX_FREQUENCY);
 	if (err)
 		goto err_devfreq;