ffmpeg: fix CVE-2023-49502

Buffer Overflow vulnerability in Ffmpeg v.n6.1-3-g466799d4f5 allows a local attacker
to execute arbitrary code via the ff_bwdif_filter_intra_c function in the
libavfilter/bwdifdsp.c:125:5 component.

Signed-off-by: Archana Polampalli <archana.polampalli@windriver.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>