[freedom-maker]: delete support for non-free hardware and emulators v0.26

the 'freedom-maker' package in the trisquel repos is not FSDG-fit - it's job is to build debian freedombox systems directly from the debian repos, for a variety of SBCs, some of which require non-free packages in the 'contrib' and 'non-free' repos - it also requires virtualbox for some bulid tartgets

so far, ive done only the FSDG and trisquel-ize patching - this MR may yet need changes