rtc: rtc-tx4939: 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>
diff --git a/drivers/rtc/rtc-tx4939.c b/drivers/rtc/rtc-tx4939.c
index 4f2c082..f9a0677 100644
--- a/drivers/rtc/rtc-tx4939.c
+++ b/drivers/rtc/rtc-tx4939.c
@@ -268,14 +268,13 @@
 	if (devm_request_irq(&pdev->dev, irq, tx4939_rtc_interrupt,
 			     0, pdev->name, &pdev->dev) < 0)
 		return -EBUSY;
-	rtc = rtc_device_register(pdev->name, &pdev->dev,
+	rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
 				  &tx4939_rtc_ops, THIS_MODULE);
 	if (IS_ERR(rtc))
 		return PTR_ERR(rtc);
 	pdata->rtc = rtc;
 	ret = sysfs_create_bin_file(&pdev->dev.kobj, &tx4939_rtc_nvram_attr);
-	if (ret)
-		rtc_device_unregister(rtc);
+
 	return ret;
 }
 
@@ -284,7 +283,6 @@
 	struct tx4939rtc_plat_data *pdata = platform_get_drvdata(pdev);
 
 	sysfs_remove_bin_file(&pdev->dev.kobj, &tx4939_rtc_nvram_attr);
-	rtc_device_unregister(pdata->rtc);
 	spin_lock_irq(&pdata->lock);
 	tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP);
 	spin_unlock_irq(&pdata->lock);