lzip: add mirror for older versions

Older versions are available in .tar.lz format from the official source but that
would cause a circular dependency on lzip-native if the host doesn't already
have lzip. Fortunately the file we need is available from FreeBSD's distfiles.

Signed-off-by: Paul Barker <paul@paulbarker.me.uk>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>