RELEASE_NOTES: mention the ffplay -autoexit behaviour change
avcodec/hevc_ps: Always initialize backup in decode_vui()

Fixes CID1237283

Reviewed-by: Christophe Gisquet <christophe.gisquet@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avfilter/af_silenceremove: remove dead code

Fixes CID1237284

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>