- Creates the zpos property.
- Implement komeda_crtc_normalize_zpos to replace
drm_atomic_normalize_zpos, reasons as the following:

1. The drm_atomic_normalize_zpos allows to configure same zpos for
different planes, but komeda doesn't support such configuration.
2. For further slave pipline case, Komeda need to calculate the
max_slave_zorder, we will merge such calculation into
komed_crtc_normalize_zpos to save a separated plane_state loop.
3. For feature none-scaling layer_split, which a plane_state will be
assigned to two individual layers(left/right), which requires two
normalize_zpos for this plane, plane_st->normalize_zpos will be used
by left layer, normalize_zpos + 1 for right_layer.

This patch series depends on:
- https://patchwork.freedesktop.org/series/58710/
- https://patchwork.freedesktop.org/series/59000/
- https://patchwork.freedesktop.org/series/59002/
- https://patchwork.freedesktop.org/series/59747/
- https://patchwork.freedesktop.org/series/59915/
- https://patchwork.freedesktop.org/series/60083/
- https://patchwork.freedesktop.org/series/60698/Signed-off-by: Lowry Li (Arm Technology China) <lowry.li@arm.com>
Reviewed-by: James Qian Wang (Arm Technology China) <james.qian.wang@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>