dt-bindings: watchdog: mediatek,mtk-wdt: add MT7988 watchdog and toprgu

dt-bindings: watchdog: mediatek,mtk-wdt: add MT7988 watchdog and toprgu

Add binding description for mediatek,mt7988-wdt.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/6478f8d2af59736d23a96b52891bb541de33870d.1700504385.git.daniel@makrotopia.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>