[PATCH 1/2] driver for Zhen Hua PCM-4CH RC transmitter v2

(again, now as attachments)

Hi,
this is a driver for Zhen Hua PCM-4CH RC transmitter (commonly used in
cheap Ready To Fly RC helicopters) which using "Zhen Hua 5-byte
protocol" for using them as a four axis joystick via serial port.

Transmitter connected to serial port (19200 8N1) sending periodically
5 bytes where first byte is for synchronization and next four bytes
are values of axis.