scripts: cleanup scripts directory

Remove unused and obsolete scripts we used with Kbuild or scripts that
were copied from Linux but never used or modified for Zephyr:

- vercomp: not needed with cmake, version comparison is built-in
- mksysmap: Linux script
- make-ll parallel build script, something that is more suitable in
  $HOME/bin, not in Zephyr tree
- headerdep.pl: Linux specific, not adapted or used with Zephyr
- timestamp: used by other checkpatch scripts under scripts/checkpatch
- move uncrustify.cfg to .uncrustify.cfg in top tree for easy access and
  alongside other configuration files.

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