The BPF-helper is now defined in bpf_helper_defs.h header:
lib/libbpf-install/usr/include/bpf/bpf_helper_defs.h
Update and keep comment as a help for people doing kernel
devel on BPF and want to test BPF-helpers not yet upstream.
Accepted in kernel v5.12
- commit 34b2021cc616 ("bpf: Add BPF-helper for MTU checking")
- https://git.kernel.org/torvalds/c/34b2021cc616
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>