rtc: rtc-efi: 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-efi.c

@@ -191,7 +191,7 @@ static int __init efi_rtc_probe(struct platform_device *dev)
 {
 	struct rtc_device *rtc;
 
-	rtc = rtc_device_register("rtc-efi", &dev->dev, &efi_rtc_ops,
+	rtc = devm_rtc_device_register(&dev->dev, "rtc-efi", &efi_rtc_ops,
 					THIS_MODULE);
 	if (IS_ERR(rtc))
 		return PTR_ERR(rtc);
@@ -203,10 +203,6 @@ static int __init efi_rtc_probe(struct platform_device *dev)
 
 static int __exit efi_rtc_remove(struct platform_device *dev)
 {
-	struct rtc_device *rtc = platform_get_drvdata(dev);
-
-	rtc_device_unregister(rtc);
-
 	return 0;
 }