OSV-2020-2061 Heap-buffer-overflow in WelsDec::WelsCheckAndRecoverForFutureDecoding

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=26301 Crash type: Heap-buffer-overflow WRITE Crash state: WelsDec::WelsCheckAndRecoverForFutureDecoding WelsDec::WelsInitRefList WelsDec::InitRefPicList...