lavfi/vf_libplacebo: generalize frame update to multiple inputs

In the event that some frame mixes are OK while others are not, the
priority goes:

1. Errors in updating any frame -> return error
2. Any input incomplete -> request frames and return
3. Any inputs OK -> ignore EOF streams and render remaining inputs
4. No inputs OK -> set output to most recent status

This logic ensures that we can continue rendering the remaining streams,
no matter which streams reach their end of life, until we have no
streams left at which point we forward the last EOF.

0 files changed, 0 insertions, 0 deletions