avcodec/clearvideo: Check tile_size to be not too large

Fixes: left shift of 1 by 31 places cannot be represented in type 'int'
Fixes: 35023/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_CLEARVIDEO_fuzzer-6740166587842560

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

libavcodec/clearvideo.c

@@ -722,8 +722,8 @@ static av_cold int clv_decode_init(AVCodecContext *avctx)
     }
 
     c->tile_shift = av_log2(c->tile_size);
-    if (1U << c->tile_shift != c->tile_size || c->tile_shift < 1) {
-        av_log(avctx, AV_LOG_ERROR, "Tile size: %d, is not power of 2 > 1\n", c->tile_size);
+    if (1U << c->tile_shift != c->tile_size || c->tile_shift < 1 || c->tile_shift > 30) {
+        av_log(avctx, AV_LOG_ERROR, "Tile size: %d, is not power of 2 > 1 and < 2^31\n", c->tile_size);
         return AVERROR_INVALIDDATA;
     }