vorbis: fix format string
opus: always sync i_buffer with i_nb_samples (fixes #10135)

Specifically, the crash at the end of playback was happening when end trim was
not being subtracted from i_buffer.
Revert "twolame: use FL32 as input"

This reverts commit 2363d00e1131bc4b50e3a15a6593e824bee68dd7.

Twolame converts from FL32 to S16 internally anyway so no point
using this instead of converting inside vlc.

Pointed-out-by: Rémi Denis-Courmont
twolame: set pf_encode at the end
faad: set decode_audio at the end
twolame: fix build after revert
Merge remote-tracking branch: upstream/master