this needs to build two images and one gzipped tar file:
- install.fs: to mdset into netbsd.INSTALL
- inst.tgz: contents of install.fs
- miniroot.fs: install.fs + gzipped GENERIC kernel. created using a
copy of the crunched ramdiskbin built for install.fs
share much of the miniroot.fs build goop from ../instfs/*
lukem