watchdog: at91sam9: Stop using module_platform_driver_probe()

On today's platforms the benefit of platform_driver_probe() isn't that
relevant any more. It allows to drop some code after booting (or module
loading) for .probe() and discard the .remove() function completely if
the driver is built-in. This typically saves a few 100k.

The downside of platform_driver_probe() is that the driver cannot be
bound and unbound at runtime which is ancient and also slightly
complicates testing. There are also thoughts to deprecate
platform_driver_probe() because it adds some complexity in the driver
core for little gain. Also many drivers don't use it correctly. This
driver for example misses to mark the driver struct with __refdata which
is needed to suppress a (W=1) modpost warning:

	WARNING: modpost: drivers/watchdog/at91sam9_wdt: section mismatch in reference: at91wdt_driver+0x4 (section: .data) -> at91wdt_remove (section: .exit.text)

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20231106154807.3866712-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

Author: Uwe Kleine-König

drivers/watchdog/at91sam9_wdt.c

@@ -324,7 +324,7 @@ static inline int of_at91wdt_init(struct device_node *np, struct at91wdt *wdt)
 }
 #endif
 
-static int __init at91wdt_probe(struct platform_device *pdev)
+static int at91wdt_probe(struct platform_device *pdev)
 {
 	int err;
 	struct at91wdt *wdt;
@@ -372,7 +372,7 @@ static int __init at91wdt_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int __exit at91wdt_remove(struct platform_device *pdev)
+static int at91wdt_remove(struct platform_device *pdev)
 {
 	struct at91wdt *wdt = platform_get_drvdata(pdev);
 	watchdog_unregister_device(&wdt->wdd);
@@ -393,14 +393,14 @@ MODULE_DEVICE_TABLE(of, at91_wdt_dt_ids);
 #endif
 
 static struct platform_driver at91wdt_driver = {
-	.remove		= __exit_p(at91wdt_remove),
+	.probe		= at91wdt_probe,
+	.remove		= at91wdt_remove,
 	.driver		= {
 		.name	= "at91_wdt",
 		.of_match_table = of_match_ptr(at91_wdt_dt_ids),
 	},
 };
-
-module_platform_driver_probe(at91wdt_driver, at91wdt_probe);
+module_platform_driver(at91wdt_driver);
 
 MODULE_AUTHOR("Renaud CERRATO <r.cerrato@til-technologies.fr>");
 MODULE_DESCRIPTION("Watchdog driver for Atmel AT91SAM9x processors");