Backport of "mxfdemux: Handle files produced by legacy FFmpeg" into 1.20
Backport of !2407 (merged) "mxfdemux: Handle files produced by legacy FFmpeg".
Commits:
- 7ac4dd3d mxfdemux: Handle files produced by legacy FFmpeg
Backport of !2407 (merged) "mxfdemux: Handle files produced by legacy FFmpeg".
Commits: