watchdog: at32watchdog: use devm_kzalloc

index 2896430..dc2e312 100644
@@ -321,7 +321,7 @@ static int __init at32_wdt_probe(struct platform_device *pdev)
 		return -ENXIO;
 	}
 
-	wdt = kzalloc(sizeof(struct wdt_at32ap700x), GFP_KERNEL);
+	wdt = devm_kzalloc(&pdev->dev, sizeof(struct wdt_at32ap700x), GFP_KERNEL);
 	if (!wdt) {
 		dev_dbg(&pdev->dev, "no memory for wdt structure\n");
 		return -ENOMEM;

@@ -329,9 +329,8 @@ static int __init at32_wdt_probe(struct platform_device *pdev)
 
 	wdt->regs = ioremap(regs->start, resource_size(regs));
 	if (!wdt->regs) {
-		ret = -ENOMEM;
 		dev_dbg(&pdev->dev, "could not map I/O memory\n");
-		goto err_free;
+		return -ENOMEM;
 	}
 
 	spin_lock_init(&wdt->io_lock);

@@ -377,9 +376,6 @@ err_register:
 	platform_set_drvdata(pdev, NULL);
 err_iounmap:
 	iounmap(wdt->regs);
-err_free:
-	kfree(wdt);
-	wdt = NULL;
 	return ret;
 }
 

@@ -392,8 +388,6 @@ static int __exit at32_wdt_remove(struct platform_device *pdev)
 
 		misc_deregister(&wdt->miscdev);
 		iounmap(wdt->regs);
-		kfree(wdt);
-		wdt = NULL;
 		platform_set_drvdata(pdev, NULL);
 	}
 	return 0;