OSV-2020-413 Stack-buffer-overflow in ot::NetworkData::NetworkDataTlv::GetNext

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=14401 Crash type: Stack-buffer-overflow READ 1 Crash state: ot::NetworkData::NetworkDataTlv::GetNext ot::NetworkData::Leader::IsStableUpdated ot::NetworkData::Leader::RegisterNetworkData...