dt-bindings: mfd: qcom,tcsr: Add sc8280xp binding

Add a binding for the SC8280XP TCSR.

Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20221007121110.5432-1-johan+linaro@kernel.org