Add a script to update the local copy of kernel headers (in include/linux/) from a Linux kernel git tree. The script handles header installation, manual processing of the IPU3 header that is still in staging, and update of the README file. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>