watchdog: mediatek: Make sure system reset gets asserted in mtk_wdt_restart()

[ Upstream commit a1495a21e0b8aad92132dfcf9c6fffc1bde9d5b2 ]

Clear the IRQ enable bit of WDT_MODE before asserting software reset
in order to make TOPRGU issue a system reset signal instead of an IRQ.

Fixes: a44a4553 ("watchdog: Add driver for Mediatek watchdog")
Signed-off-by: Yassine Oudjana <y.oudjana@protonmail.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20241106104738.195968-2-y.oudjana@protonmail.com


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