configs/releng/airootfs/etc/systemd/system/multi-user.target.wants/iwd.service: Adding a symlink to /usr/lib/systemd/system/iwd.service to enable iwd in airootfs (and thus on the image). Closes #18
Two purposes: * systemd filename friendly: "-" is used for "/" and must be escaped with "\x20" * ISO9660 filename friendly: "-" is replaced with "_"