test/klibc: new aport

To be able to offer super minimalistic systems, or really just early boot, klibc offers a limited subsect of utilities. Just enough to bring up a rootfs. It is like a tiny busybox.

This could also help in the future where people want to have super minimalistic containers (FROM scratch) but still want to offer some basics (sh and maybe slightly more) to help with CI runners.

Signed-off-by: Olliver Schinagl oliver@schinagl.nl