dt-bindings: mailbox: qcom: add compatible for IPQ9574 SoC

Add the mailbox compatible for IPQ9574 SoC.
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Devi Priya <quic_devipriy@quicinc.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Documentation/devicetree/bindings/mailbox/qcom,apcs-kpss-global.yaml

@@ -20,6 +20,7 @@ properties:
           - enum:
               - qcom,ipq5332-apcs-apps-global
               - qcom,ipq8074-apcs-apps-global
+              - qcom,ipq9574-apcs-apps-global
           - const: qcom,ipq6018-apcs-apps-global
       - items:
           - enum: