arm64: dts: mt8195: Disable watchdog external reset signal

Disable the external output reset signal of watchdog reset to avoid losing
the reset reason stored in the watchdog registers.
Signed-off-by: Fengquan Chen <fengquan.chen@mediatek.com>
Signed-off-by: Tinghan Shen <tinghan.shen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220811025813.21492-9-tinghan.shen@mediatek.comSigned-off-by: Matthias Brugger <matthias.bgg@gmail.com>

arch/arm64/boot/dts/mediatek/mt8195.dtsi

@@ -327,6 +327,7 @@ pio: pinctrl@10005000 {
 		watchdog: watchdog@10007000 {
 			compatible = "mediatek,mt8195-wdt",
 				     "mediatek,mt6589-wdt";
+			mediatek,disable-extrst;
 			reg = <0 0x10007000 0 0x100>;
 		};