watchdog: at91rm9200: Only warn once about problems in .remove()

The single difference between returning 0 and returning an error code in
a platform remove callback is that in the latter case the platform core
emits a warning about the error being ignored.

at91wdt_remove() already emits a warning in the error case, so suppress
the more generic (and less helpful) one by returning 0.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230217095317.1213387-1-u.kleine-koenig@pengutronix.de


Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>