ofono: implement abstraction for the radio settings interface

Open-WebOS-DCO-1.0-Signed-Off-By: Simon Busch <morphis@gravedo.de>
Implement service ratQuery API method

Open-WebOS-DCO-1.0-Signed-Off-By: Simon Busch <morphis@gravedo.de>
ofono: implement ratQuery API method

Open-WebOS-DCO-1.0-Signed-Off-By: Simon Busch <morphis@gravedo.de>