PM / devfreq: Mute warning on governor PROBE_DEFER

Don't print warning when a governor PROBE_DEFER as it's not a real
GOV_START fail.

Fixes: a03dacb0 ("PM / devfreq: Add cpu based scaling support to passive governor")
Signed-off-by: Christian 'Ansuel' Marangi <ansuelsmth@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

drivers/devfreq/devfreq.c

@@ -932,8 +932,9 @@ struct devfreq *devfreq_add_device(struct device *dev,
 	err = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_START,
 						NULL);
 	if (err) {
-		dev_err(dev, "%s: Unable to start governor for the device\n",
-			__func__);
+		dev_err_probe(dev, err,
+			"%s: Unable to start governor for the device\n",
+			 __func__);
 		goto err_init;
 	}
 	create_sysfs_files(devfreq, devfreq->governor);