Some minor changes to Makefile to allow building TrueNAS or
FreeNAS depending on NANO_LABEL, rather than having the single
truenas target.

This allows the other changes:  changes to allow TrueNAS to be
updatified, and pushed to an update server.  (Currently the
same system.)
Merge branch 'master' of gitserver.ixsystems.com:/git/repos/freenas-build/freenas