First step for adding the new board layer. Create configurations for the
various boards we support on x86 under boards with the new Kconfig variables
defining them.
The board selection is optional, that means you will be able to run
make menuconfig
and create your own .config and select any SoC.
Change-Id: If08e88e9675d13f0f0501ef6750b9424b15f5dc8
Signed-off-by: Anas Nashif <anas.nashif@intel.com>