OSV-2026-354 Use-of-uninitialized-value in pcpp::MplsLayer::toString

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=489360236 Crash type: Use-of-uninitialized-value Crash state: pcpp::MplsLayer::toString FuzzTarget.cpp pcpp::RawPacket::RawPacket...