rtc: rtc-sun4v: 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-sun4v.c

@@ -81,8 +81,10 @@ static const struct rtc_class_ops sun4v_rtc_ops = {
 
 static int __init sun4v_rtc_probe(struct platform_device *pdev)
 {
-	struct rtc_device *rtc = rtc_device_register("sun4v", &pdev->dev,
-				     &sun4v_rtc_ops, THIS_MODULE);
+	struct rtc_device *rtc;
+
+	rtc = devm_rtc_device_register(&pdev->dev, "sun4v",
+				&sun4v_rtc_ops, THIS_MODULE);
 	if (IS_ERR(rtc))
 		return PTR_ERR(rtc);
 
@@ -92,9 +94,6 @@ static int __init sun4v_rtc_probe(struct platform_device *pdev)
 
 static int __exit sun4v_rtc_remove(struct platform_device *pdev)
 {
-	struct rtc_device *rtc = platform_get_drvdata(pdev);
-
-	rtc_device_unregister(rtc);
 	return 0;
 }