dt-bindings: mmc: sdhci-msm: Document compatible for MSM8976

Document the compatible for the SDHCI controller(s) found on MSM8976.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20221104172122.252761-6-angelogioacchino.delregno@collabora.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/sdhci-msm.yaml

@@ -26,6 +26,7 @@ properties:
               - qcom,msm8226-sdhci
               - qcom,msm8953-sdhci
               - qcom,msm8974-sdhci
+              - qcom,msm8976-sdhci
               - qcom,msm8916-sdhci
               - qcom,msm8992-sdhci
               - qcom,msm8994-sdhci