execline

• --enable-multicall reduces disk usage, and barely increases resource usage (skarnet uses it on lh-bootstrap and Alpine): https://skarnet.org/software/execline/execline.html
• multicall is disabled on Adelie: https://git.adelielinux.org/adelie/packages/-/commit/b915ccf477dbb0bc2ec2fe6876d44722a55f4d4a
• There is no test suite
• check if we need to provide --with- flags in Dependencies section for native builds as well (not just for build-cross)