SubPicAP: Correct yuvMatrix implementation.

Only supports VMR9 and EVR-CP for now, need to improve access to MediaType.
Requires new build of LAV that gives access to extended color information.
Squash with 0e0229109e755faaa2c0975fc4b2cf0c2eb5220b.
SubPicAP: Disable subpic buffer for XySubFilter.