Where possible, keep the same style for returning error. Change-Id: I3a04220c0b9f129a36e9fe83038b7c19dd57fe61 Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com> Reviewed-on: http://openocd.zylin.com/4699 Tested-by: jenkins Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>master