Support Homestar rev4 board where Parade ps8640 is added as the
second source edp bridge.

Support different edp bridge chips in different board revisions,
now we move the #incldue line of the edp bridge dts fragment (e.g.
sc7180-trogdor-ti-sn65dsi86.dtsi) from "sc7180-trogdor-homestar.dtsi"
to per-board-rev dts files.

Since the edp bridge dts fragment overrides 'dsi0_out', which is
defined in "sc7180.dtsi", move the #incldue line of "sc7180.dtsi" from
"sc7180-trogdor-homestar.dtsi" to per-board-rev dts files too, before
the #include line of the edp bridge dts fragment.
Signed-off-by: Philip Chen <philipchen@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20211029152647.v3.4.If7aaa8e36f1269acae5488035bd62ce543756bf8@changeid