Refactored how the usrp2/firmware connects into the top-level built.
We now have "normal" behavior. That is, if your current directory is
usrp2, when you invoke "make" it will make both the host and firmware
git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@9709 221aa14e-8319-0410-a670-987f0aec2ac5