libs/web: fix sanitize_utf8(), passes all testcases now
libs/web: fix sanitize_utf8(), passes all testcases now


deepak78/luci,8devices/luci,8devices/luci,deepak78/luci,deepak78/luci,deepak78/luci,8devices/luci,deepak78/luci,8devices/luci,8devices/luci,8devices/luci,deepak78/luci,deepak78/luci,deepak78/luci