Add komeda_kms abstracton to attach komeda_dev to DRM-KMS
  CRTC: according to the komeda_pipeline
  PLANE: according to komeda_layer (layer input pipeline)
  PRIVATE_OBJS: komeda_pipeline/component all will be treat as private_objs

komeda_kms is for connecting DRM-KMS and komeda_dev, like reporting the
kms object properties according to the komeda_dev, and pass/convert KMS's
requirement to komeda_dev.

Changes in v4:
- Set drm_atomic_helper_check as mode_config->atomic_check.

Changes in v3:
- Fixed style problem found by checkpatch.pl --strict.

Changes in v2:
- Unified abbreviation of "pipeline" to "pipe".
Signed-off-by: James Qian Wang (Arm Technology China) <james.qian.wang@arm.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>