spatializer: integrate pose controller

Implement head tracking functions in Spatializer
class based on the SpatializerPoseController class.

Add new APIs to ISpatializer interface to:
- set head pose sensor
- set screen pose sensor
- set screen orientation
Add new APIs to INativeSpatializerCallback to:
- notify new head to stage pose
- notify new actual headtracking mode

Bug: 188502620
Test: manual test with mock spatializer
Change-Id: I4584df055cd91bc124d081861baa2fe83df69fa5