USB OTG Console (not adb shell)

need console over usb without ADB, like ttyGS0.
phh reply on irc and post this script https://gist.github.com/phhusson/fa8cfecc73bc26090d61784dfbccfcf6 (big thx phh!).
but i dont know how apply this script on installed official debian image. (this init.d script or i wrong?)
please help.