rtc: rtc-ds1672: use devm_rtc_device_register()

devm_rtc_device_register() is device managed and makes cleanup paths
simpler.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-ds1672.c

@@ -155,11 +155,6 @@ static const struct rtc_class_ops ds1672_rtc_ops = {
 
 static int ds1672_remove(struct i2c_client *client)
 {
-	struct rtc_device *rtc = i2c_get_clientdata(client);
-
-	if (rtc)
-		rtc_device_unregister(rtc);
-
 	return 0;
 }
 
@@ -177,7 +172,7 @@ static int ds1672_probe(struct i2c_client *client,
 
 	dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n");
 
-	rtc = rtc_device_register(ds1672_driver.driver.name, &client->dev,
+	rtc = devm_rtc_device_register(&client->dev, ds1672_driver.driver.name,
 				  &ds1672_rtc_ops, THIS_MODULE);
 
 	if (IS_ERR(rtc))
@@ -202,7 +197,6 @@ static int ds1672_probe(struct i2c_client *client,
 	return 0;
 
  exit_devreg:
-	rtc_device_unregister(rtc);
 	return err;
 }