dt-bindings: dma: qcom: gpi: add compatible for sdm670

The Snapdragon 670 uses GPI DMA for its GENI interface. Add a compatible
string for it in the documentation.
Signed-off-by: Richard Acayan <mailingradian@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221018005740.23952-3-mailingradian@gmail.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

Documentation/devicetree/bindings/dma/qcom,gpi.yaml

@@ -27,6 +27,7 @@ properties:
           - qcom,sm8450-gpi-dma
       - items:
           - enum:
+              - qcom,sdm670-gpi-dma
               - qcom,sm8150-gpi-dma
               - qcom,sm8250-gpi-dma
           - const: qcom,sdm845-gpi-dma