dt-bindings: watchdog: Document Qualcomm SM6115 watchdog

Add devicetree binding for watchdog present on Qualcomm
SM6115 SoC.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230314051351.1754321-1-bhupesh.sharma@linaro.org


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