dt-bindings: watchdog: mtk-wdt: Add reset-by-toprgu support

dt-bindings: watchdog: mtk-wdt: Add reset-by-toprgu support

In some applications, the mtk-wdt requires the TOPRGU (Top Reset
Generation Unit) to reset timer after system resets. Add optional
mediatek,reset-by-toprgu property to enable it.

Signed-off-by: Allen-KH Cheng <allen-kh.cheng@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230117014023.2993-2-allen-kh.cheng@mediatek.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>