[PATCH net 2/2] wireguard: selftests: add metadata_dst xmit selftest

[Jason A. Donenfeld]

Hi Nikolay,

These tests need to run in the minimal fast-to-compile test harness
inside of tools/testing/selftests/wireguard/qemu, which you can try
out with:

$ make -C tools/testing/selftests/wireguard/qemu -j$(nproc)

Currently iproute2 is built, but only ip(8) is used in the image, so
you'll need to add tc(8) to there. Clang, however, seems a bit
heavyweight. I suspect it'd make more sense to just base64 up that
object file and include it as a string in the file? Or, alternatively,
we could just not move ahead with this rather niche test, and revisit
the issue if we wind up wanting to test for lots of bpf things.
Thoughts on that?

Jason