This patchset enables both detecting as well as dumping compilable prototypes for kfuncs. The first commit instructs pahole to DECL_TAG kfuncs when available. This requires v1.27 which was released on 6/11/24. With it, users will be able to look at BTF inside vmlinux (or modules) and check if the kfunc they want is available. The final commit teaches bpftool how to dump kfunc prototypes. This is done for developer convenience. The rest of the commits are fixups to enable selftests to use the newly dumped kfunc prototypes. With these, selftests will regularly exercise the newly added codepaths. Tested with and without the required pahole changes: * https://github.com/kernel-patches/bpf/pull/7186 * https://github.com/kernel-patches/bpf/pull/7187 === Changelog ===
