Add Arch Linux

[pataquets]

Quite popular distro which would be very useful to have as an option. Awesome software. Thanks for sharing.

[IsaacSchemm]

Does this look right? https://archlinux.org/releng/netboot/

If so, it shouldn't be too hard to add that ipxe.lrkn to the menu, at least once I get around to it (if anyone else wants to send in a merge request in the meantime, feel free)

[spcwingo]

I have added Arch and it has been merged. ;-)

[pataquets]

Thanks a lot @spcwingo! I've not been able to figure out how to add ArchLinux32 myself, since I didn't found the relevant 32-bit files. I've posted this to ArchLinux32 forums: https://bbs.archlinux32.org/viewtopic.php?pid=9790