scripts: add configuration file for uncrustify

Use this configuration file with the uncrustify tool to fix style
issues. the configuration should apply the zephyr coding style on
source code files with a few minor excrption. Do not take the output for
granted, always check for correctness after running.

To use, for example:

uncrustify --replace --no-backup -l C -c $ZEPHYR_BASE/scripts/uncrustify.conf

This will do the changes inline.

Change-Id: Iecfd2e10bc7e475ca83de0d921ebb5d72156d286
Signed-off-by: Anas Nashif <anas.nashif@intel.com>