kconfig: rename non-Kconfig CONFIG_* variables

CONFIG_* usually come from Kconfig, rename variables that are locally
defined to avoid confusion about where they are set.

Change-Id: I83b8459913c5deb68dc1b9f5386b8934363a6d1f
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
4 files changed