watchdog: advantechwdt: Use platform_driver_probe

Using platform_driver_probe instead of platform_driver_register has
two benefits:
* The driver will fail to load if device probing fails.
* The probe function can be marked __init.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
diff --git a/drivers/watchdog/advantechwdt.c b/drivers/watchdog/advantechwdt.c
index a8961ad..7796db7 100644
--- a/drivers/watchdog/advantechwdt.c
+++ b/drivers/watchdog/advantechwdt.c
@@ -238,7 +238,7 @@
  *	Init & exit routines
  */
 
-static int advwdt_probe(struct platform_device *dev)
+static int __init advwdt_probe(struct platform_device *dev)
 {
 	int ret;
 
@@ -299,7 +299,6 @@
 }
 
 static struct platform_driver advwdt_driver = {
-	.probe		= advwdt_probe,
 	.remove		= advwdt_remove,
 	.shutdown	= advwdt_shutdown,
 	.driver		= {
@@ -314,21 +313,19 @@
 
 	pr_info("WDT driver for Advantech single board computer initialising\n");
 
-	err = platform_driver_register(&advwdt_driver);
-	if (err)
-		return err;
-
 	advwdt_platform_device = platform_device_register_simple(DRV_NAME,
 								-1, NULL, 0);
-	if (IS_ERR(advwdt_platform_device)) {
-		err = PTR_ERR(advwdt_platform_device);
-		goto unreg_platform_driver;
-	}
+	if (IS_ERR(advwdt_platform_device))
+		return PTR_ERR(advwdt_platform_device);
+
+	err = platform_driver_probe(&advwdt_driver, advwdt_probe);
+	if (err)
+		goto unreg_platform_device;
 
 	return 0;
 
-unreg_platform_driver:
-	platform_driver_unregister(&advwdt_driver);
+unreg_platform_device:
+	platform_device_unregister(advwdt_platform_device);
 	return err;
 }