sdm: Remove LayerCache from HWC

- Move LayerCache to SDM and remove it from HWC
- At the end of prepare, HWC will just translate SDM comp types
  to HWC types
- Initialize layers plane_alpha to 0xff(default) to avoid setting
  to 0xff every time.
- Add updating field to HWLayersInfo which is updated by strategy
  and can be used by other modules(rotator)
- Add Reconfigure to Strategy

Change-Id: Id497330a55b953cb56a4f8a918e169dcdba7f707
Crs-fixed: 1011136
8 files changed