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.org


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>