artix/other arch based systems with different repo names

[kreciorek]

when i tried to install, it recognized it as arch and i didint think much of it, but it was trying to add multi-lib repo when on artix its lib32.
it looks like this
Artix | Arch
-- | --
system | core
world | extra
lib32 | multilib
so basically it fails since theres no repo as multilib.
in fact u can get arch repos but they dont work for some reason.

[NelloKudo]

I guess I'll need to add a check for Artix as well. Thanks for noticing!