Justin, Vinayak,

Thanks, still digging into this.  So far, the cmake phase is not properly copying the
drivers into the library and failing before any make files are produced.  So, menuconfig
will not run on the project.  The driver CMakeLists.txt seems to be correct, but the value
CONFIG_SPI is not being set (I assume because of a DTS issue) and therefore the
source/library environment is not being properly generated by the initial project
cmake command.

Have performed the same operation with arduino_101 target and things work.  Don't
have one of those boards, so can't say that target code runs.  But, cmake and make
phase run successfully.  Have been comparing dts and dtsi files (should I be looking at
yaml as well?) between arduino_101 and nrf52840_pca10056 to look for an answer.
But, no joy as yet.  Any suggestions from the group?

Cheers,
Chuck