dt-bindings: display/msm: dsi-controller-main: Fix deprecated QCM2290 compatible

The point of the previous cleanup was to disallow "qcom,mdss-dsi-ctrl"
alone. This however didn't quite work out and the property became
undocumented instead of deprecated. Fix that.

Additionally, the "qcom," prefix was missed previously. Fix it.

Fixes: 0c0f65c6 ("dt-bindings: msm: dsi-controller-main: Add compatible strings for every current SoC")
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/527651/
Link: https://lore.kernel.org/r/20230307-topic-dsi_qcm-v6-1-70e13b1214fa@linaro.orgSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

Documentation/devicetree/bindings/display/msm/dsi-controller-main.yaml

@@ -31,10 +31,9 @@ properties:
               - qcom,sm8450-dsi-ctrl
               - qcom,sm8550-dsi-ctrl
           - const: qcom,mdss-dsi-ctrl
-      - items:
-          - enum:
-              - dsi-ctrl-6g-qcm2290
-          - const: qcom,mdss-dsi-ctrl
+      - enum:
+          - qcom,dsi-ctrl-6g-qcm2290
+          - qcom,mdss-dsi-ctrl # This should always come with an SoC-specific compatible
         deprecated: true
 
   reg: