ffmpeg: Index-out-of-bounds in add_candidate_ref

Project: https://git.ffmpeg.org/ffmpeg.git Detailed report: https://oss-fuzz.com/testcase?key=5012343912136704 Project: ffmpeg Fuzzer: libFuzzerffmpegAVCODECIDHEVCfuzzer Fuzz target binary: ffmpegAVCODECIDHEVCfuzzer Job Type: libfuzzerubsanffmpeg Platform Id: linux Crash Type: Index-out-of-bounds...