dt-bindings: mediatek: mt2712: Add #reset-cells

Add #reset-cells and update mtk-wdt.txt

Signed-off-by: yong.liang <yong.liang@mediatek.com>
Signed-off-by: Jiaxin Yu <jiaxin.yu@mediatek.com>
Reviewed-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Guenter Roeck <groeck7@gmail.com>
Link: https://lore.kernel.org/r/20200115085828.27791-3-yong.liang@mediatek.com


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