tcp*.bt scripts tried to include glibc headers, which didn't work on
nixos because bpftrace tried to call clang-major with some options to
get the paths, but we never told it where to find it.
Give bpftrace the path directly instead of giving it a path to clang.
runqlat.bt doesn't work with glibc headers and requires kernel headers
which are no longer extracted, just provide its value.
Note the default clang output also had some clang-internal headers, but
these seem to be included anyway through libclang API without having to
give them here, so we only pass the glibc ones.
While here:
- also backport another bpftrace patch that made the tcp*.bt tools to
actually not require these includes
- and add tests that we can include these.
Co-authored-by: Arian van Putten <arian.vanputten@gmail.com>