It's been confusing to say the least, resulting in multiple
misuses throughout the code.  The idea was that /cf pointed
to a read-write root, while / pointed to read-only root.
For non-embedded images this was emulated by linking
/conf -> /cf/conf, which, is a bit questionable because now
you can write from /conf as well and don't have to use /cf/conf
at all.

A couple of lines are left in /usr/local/etc/rc which need to
be reviewed so that migration paths are safe for all types
of firmware upgrades.