libbpf: Avoid enum forward-declarations in public API in C++ mode
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v5.15.86 by commit 474e70bd90cf89116ae5f6b9c0e9a459626eaffe. For more details please see the references link.