Parse iprp and iinf boxes and its child boxes to get the actual codec used
(AV1 for avif, HEVC for heic), and properly export extradata and other
properties in a generic way.
The avif tests reference files are updated as the extradata is now exported.
Based on a patch by Swaraj Hota
Co-authored-by: Swaraj Hota <swarajhota353@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>