Refactor the prj*conf files so that there is only one master
prj.conf and several overlay conf files that add / change
only minor subset of functionality.
Use the overlay files like so:
cmake -DBOARD=nrf52840_pca10056 \
-DOVERLAY_CONFIG=overlay-ot.conf ..
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Jukka Rissanen