wnv1: remove unused avctx from codec private context

Signed-off-by: Paul B Mahol <onemda@gmail.com>
kgv1dec: make decoder independent of sizeof(AVFrame)

Signed-off-by: Paul B Mahol <onemda@gmail.com>
kgv1dec: remove unused avctx from codec private context

Signed-off-by: Paul B Mahol <onemda@gmail.com>
vformat/subtitles: check av_copy_packets return code

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/avpacket: Use av_free_packet() in error cleanups

This prevents memleaks on errors
reproduceable with fate when error pathes are forced

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>