dt-bindings: soundwire: qcom: Document v3.1.0 version of IP block

Add bindings for Soundwire controllers v3.1.0, which is available on
Qualcomm Glymur SoC.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Tested-by: Alexey Klimov <alexey.klimov@linaro.org> # sm8550
Link: https://patch.msgid.link/20250912083225.228778-7-srinivas.kandagatla@oss.qualcomm.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Author: Srinivas Kandagatla

Documentation/devicetree/bindings/soundwire/qcom,soundwire.yaml

@@ -23,6 +23,7 @@ properties:
           - qcom,soundwire-v1.6.0
           - qcom,soundwire-v1.7.0
           - qcom,soundwire-v2.0.0
+          - qcom,soundwire-v3.1.0
       - items:
           - enum:
               - qcom,soundwire-v2.1.0