Make SetChapterBag consistent, reduce duplication.
Invalidate control when ChapterBag is changed.
GetEventString: Add DVD-Video and sound device event codes.
madVR: Hook DXVA decoder to have status and logging.
Use IID_PPV_ARGS whether possible.
Improve the reliability of the [DXVA] indicator in the status bar.

Sometimes the indicator wasn't shown while hardware acceleration was used.

This commit fixes #3518.
Get the DXVA status once and for all when opening the file.

No need to check it every time the status bar is updated.
Support for multiple programs in one IFO file.

WIP