Add Arch support to --initial-setup
As per https://bugs.kde.org/show_bug.cgi?id=402484, Arch/Manjaro require perl-io-socket-ssl
rather than whatever other package kdesrc-build is trying to pick up.
As per https://bugs.kde.org/show_bug.cgi?id=402484, Arch/Manjaro require perl-io-socket-ssl
rather than whatever other package kdesrc-build is trying to pick up.