dt-bindings: watchdog: Document X1E80100 compatible

dt-bindings: watchdog: Document X1E80100 compatible

Document the compatible for the X1E80100 platform to the Qualcomm watchdog
binding. The HW implementation is compatible with the KPSS WDT.

Acked-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20251224-arm64-dts-qcom-x1e80100-el2-add-apss-wdt-v3-1-1801c55d2883@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>