Document the bindings for the Qualcomm QCM6490 IDP and QCS6490 RB3Gen2
board specific sound card.

The bindings are the same as for other newer Qualcomm ADSP sound cards,
thus keep them in existing qcom,sm8250.yaml file, even though Linux driver
is separate.
Signed-off-by: Mohammad Rafi Shaik <quic_mohs@quicinc.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://msgid.link/r/20240408042331.403103-2-quic_mohs@quicinc.comSigned-off-by: Mark Brown <broonie@kernel.org>