The SoC is always present on sc7180-trogdor.dtsi and thus we should
include it in the "generic" dtsi file for trogdor. Previously we had
removed it from there because we had to do the spi6/spi0 swizzle, so
each trogdor variant board had to include sc7180.dtsi and then
sc7180-trogdor.dtsi so that the latter dtsi file could modify the right
spi bus for EC and H1 properties that are common to all trogdor boards.

Now that we're done with that we can replace sc7180.dtsi includes with
sc7180-trogdor.dtsi and include sc7180.dtsi in sc7180-trogdor.dtsi as
was originally intended. We still need to include sc7180-trogdor.dtsi
before the bridge dtsi files though because those rely on the panel
label.

Cc: "Joseph S. Barrera III" <joebar@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220427020339.360855-4-swboyd@chromium.org