graphics/pqiv: Fix build with FFmpeg 8.0

Backport upstream commits a36571549a32d2ec41d6f523d443de74e0fb1276
and fc4f1767ee72e3f9cc7c0f7945da6a05b56db458

References:
https://github.com/phillipberndt/pqiv/commit/a36571549a32d2ec41d6f523d443de74e0fb1276
https://github.com/phillipberndt/pqiv/commit/fc4f1767ee72e3f9cc7c0f7945da6a05b56db458

PR: 289506
Approved by: blanket, build fix