this header is used in numerous files and adding to config.h simplifies its use globally. Change-Id: Id724a9950b90504721233022c7fb5768e9bc5548 Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk> Reviewed-on: http://openocd.zylin.com/649 Tested-by: jenkins Reviewed-by: Xiaofan <xiaofanc@gmail.com>tags/v0.6.0-rc1