Use packed bigarray in ffmpeg swscale calls. #11689

Job	Run time
build_details	2s
build_js	44s
build_opam (4.14.x)	44s
build_opam (5.2.x)	46s
tree_sitter_parse	46s
lezer_parse	47s
build_no_depopts	35s
build_posix (debian_trixie, amd64)	11s
build_win32 (x64)	35s
run_tests (@citest)	34s
build_posix (debian_bookworm, amd64)	16s
build_posix (ubuntu_oracular, amd64)	5s
run_tests (@doctest)	34s
build_posix (ubuntu_noble, amd64)	1s
run_tests (@mediatest)	34s
build_posix (alpine, amd64)	35s
update_doc	0s
fetch_s3_artifacts	1s
update_release	1s
build_docker	1s
build_docker_alpine	1s
build_docker_alpine_minimal	1s
build_docker_minimal	1s
build_docker_release	1s
build_docker_release-minimal	1s
	7m 57s

Provide feedback