dt-bindings: watchdog: mtk-wdt: add disable_wdt_extrst support

This patch add a description and example of disable_wdt_extrst
element for watchdog on MTK Socs

Signed-off-by: Fengquan Chen <[email protected]>
Acked-by: Rob Herring <[email protected]>
Reviewed-by: Guenter Roeck <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Guenter Roeck <[email protected]>
Signed-off-by: Wim Van Sebroeck <[email protected]>

Author: mtk23002

Documentation/devicetree/bindings/watchdog/mtk-wdt.txt

@@ -22,6 +22,7 @@ Required properties:
 - reg : Specifies base physical address and size of the registers.
 
 Optional properties:
+- mediatek,disable-extrst: disable send output reset signal
 - interrupts: Watchdog pre-timeout (bark) interrupt.
 - timeout-sec: contains the watchdog timeout in seconds.
 - #reset-cells: Should be 1.
@@ -31,6 +32,7 @@ Example:
 watchdog: watchdog@10007000 {
 	compatible = "mediatek,mt8183-wdt",
 		     "mediatek,mt6589-wdt";
+	mediatek,disable-extrst;
 	reg = <0 0x10007000 0 0x100>;
 	interrupts = <GIC_SPI 139 IRQ_TYPE_NONE>;
 	timeout-sec = <10>;