ffmpeg: upgrade 7.1.1 -> 7.1.2
Fixes CVE-2025-7700
Changelog:
https://github.com/FFmpeg/FFmpeg/blob/n7.1.2/Changelog
(From OE-Core rev: b564d34603753e93fdd52fc73c901a0d423c9681)
Signed-off-by: Archana Polampalli <archana.polampalli@windriver.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>