- Don't rename libbpf's bpf_map_def struct, and distribute the needed bpf
headers.
The bpf_map_def struct has been deprecated for quite some time now,
and it was been removed on >= 6.2 anyway.
We still need it, because we use gobpf.
- Improved compilation behaviour:
- We don't require the kernel sources anymore. We can just use the
kernel headers from the distribution.
- There's no need to copy the sources to the kernel tree, the modules
can be compiled from the ebpf_prog/ dir.
- Compiling against kernels 6.x seems to solve the problem we had with
VPNs, where connections were not intercepted with modules compiled
against 5.8, on kernels >= 5.19.
The modules has been tested on kernels 4.17, 5.4, 5.10, 5.15, 6.1 and
6.2 (kernel connections included).
Closes: #939
