avcodec/dxv: Check remaining bytes in dxv_decompress_raw()

Fixes: Timeout
Fixes: 2006/clusterfuzz-testcase-minimized-5766515037044736

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

libavcodec/dxv.c

@@ -335,6 +335,9 @@ static int dxv_decompress_raw(AVCodecContext *avctx)
     DXVContext *ctx = avctx->priv_data;
     GetByteContext *gbc = &ctx->gbc;
 
+    if (bytestream2_get_bytes_left(gbc) < ctx->tex_size)
+        return AVERROR_INVALIDDATA;
+
     bytestream2_get_buffer(gbc, ctx->tex_data, ctx->tex_size);
     return 0;
 }