drm/komeda: Add the initial scaler support for CORE

This patch add the initial and necessary logic for CORE to support scaler:
- Complete the struct komeda_scaler and komeda_scaler_state for adding
  the scaler specific features and capablities.
- Implement komeda_scaler_validate to check the scaler with the data flow
  configurations.
- Enable scaling support for plane input path (layer input data flow).

v2: Fix a typo, and rename "needs_scaling" to "en_scaling"

Signed-off-by: James Qian Wang (Arm Technology China) <james.qian.wang@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>