ksdk: Add Makefile support for ksdk device and CPU

Translate the SOC name and part number into the ksdk device path and CPU
macro respectively. This will be used by future ksdk shim drivers and by
the ksdk itself.

Change-Id: I40e94441ee032bfbed7df834be8000d95be53250
Signed-off-by: Maureen Helm <maureen.helm@nxp.com>