dt-bindings: display/msm: hdmi: mark old GPIO properties as deprecated

Mark obsolete GPIO properties as deprecated. They are not used by
existing device trees. While we are at it, also drop them from the
schema example.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/488852/
Link: https://lore.kernel.org/r/20220609122350.3157529-3-dmitry.baryshkov@linaro.orgSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

Documentation/devicetree/bindings/display/msm/hdmi.yaml

@@ -66,14 +66,17 @@ properties:
 
   qcom,hdmi-tx-mux-en-gpios:
     maxItems: 1
+    deprecated: true
     description: HDMI mux enable pin
 
   qcom,hdmi-tx-mux-sel-gpios:
     maxItems: 1
+    deprecated: true
     description: HDMI mux select pin
 
   qcom,hdmi-tx-mux-lpm-gpios:
     maxItems: 1
+    deprecated: true
     description: HDMI mux lpm pin
 
   '#sound-dai-cells':