Building GNU Radio with a cross compiler

I’ve spent a good aprt of the week cleaning up processes for building
GNU Radio for ARM targets using OpenEmbedded (a part of the Yocto

First, some instructions for building GNU radio. This approach usses the
repo tool to manage the various layers needed to build gnuradio.

Next we have notes on using an sdk from OE to build gnuradio on your
desktop and running make test.

We still need to look at OOT modules and installing stuff on the target
after building. I have some ideas, but I wanted to get some more eyes on
the overall processes. The cmake toolchain file is in gnuradio/master

This is a good time to ask people hwo we should organize the embedded
working group, if you have ideas, let me know. We can start to organize
ourselves after the Thanksgiving holiday next week.