[3.0] ffmpeg: fix DXVA2/D3D11 crash on bogus references
Fixes #26738
(cherry picked from commit 1e0b78a9) (edited) edited:
- on 3.0 the patch needs to be set on FFmpeg only
- the emscripten patch before this one is not on 3.0
Fixes #26738
(cherry picked from commit 1e0b78a9) (edited) edited:
VideoLAN code repository instance