avformat/bintext: Check width

Fixes: division by 0
Fixes: 26780/clusterfuzz-testcase-minimized-ffmpeg_dem_ADF_fuzzer-5117945027756032
Fixes: 26998/clusterfuzz-testcase-minimized-ffmpeg_dem_ADF_fuzzer-5119352359354368

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit f6dc285fb5)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavformat/bintext.c

@@ -293,6 +293,8 @@ static int adf_read_header(AVFormatContext *s)
         bin->fsize = avio_size(pb) - 1 - 192 - 4096;
         st->codecpar->width = 80<<3;
         ff_sauce_read(s, &bin->fsize, &got_width, 0);
+        if (st->codecpar->width < 8)
+            return AVERROR_INVALIDDATA;
         if (!bin->width)
             calculate_height(st->codecpar, bin->fsize);
         avio_seek(pb, 1 + 192 + 4096, SEEK_SET);