The variable substitution used to parse the clang version was a bashism, so
it broke on Debian/Ubuntu. So let's just use sed instead.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Seems some distributions will change the clang version output to be
something like 'Ubuntu clang version
12.0.1-++20210918042554+fed41342a82f-1~exp1~20210918143322.141'. Fix the
version parsing in configure to not barf on such weird version strings.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
The dhcp-relay utility was initially implemented as part of the
bpf-examples repository, but really belongs here. So import it along with
the build environment from bpf-examples.
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
