PM / devfreq: Propagate error from devfreq_add_device()

Propagate the error of devfreq_add_device() in devm_devfreq_add_device()
rather than statically returning ENOMEM. This makes it slightly faster
to pinpoint the cause of a returned error.

Fixes: 8cd8409 ("PM / devfreq: Add resource-managed function for devfreq device")
Cc: stable@vger.kernel.org
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>

drivers/devfreq/devfreq.c

@@ -737,7 +737,7 @@ struct devfreq *devm_devfreq_add_device(struct device *dev,
 	devfreq = devfreq_add_device(dev, profile, governor_name, data);
 	if (IS_ERR(devfreq)) {
 		devres_free(ptr);
-		return ERR_PTR(-ENOMEM);
+		return devfreq;
 	}
 
 	*ptr = devfreq;