Revert "drm: Introduce solid fill DRM plane property"

This reverts commit 85863a4e

.

Although the Solid Fill planes patchset got all reviews and
acknowledgements, it doesn't fulfill requirements for the new uABI. It
has neither corresponding open-source userspace implementation nor the
IGT tests coverage. Reverting this patchset until userspace obligations
are fulfilled.

Acked-by: Simon Ser <contact@emersion.fr>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231204131455.19023-7-dmitry.baryshkov@linaro.org