avformat/mov: Check that is_still_picture_avif has no trak based streams

Fixes: Assertion failure in mov_read_iloc( in mov_read_iloc())
Fixes: 62866/clusterfuzz-testcase-minimized-ffmpeg_dem_MOV_fuzzer-5282997370486784

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

libavformat/mov.c

@@ -4628,6 +4628,10 @@ static int mov_read_trak(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     MOVStreamContext *sc;
     int ret;
 
+    if (c->is_still_picture_avif) {
+        return AVERROR_INVALIDDATA;
+    }
+
     st = avformat_new_stream(c->fc, NULL);
     if (!st) return AVERROR(ENOMEM);
     st->id = -1;