Add support for setting Sainsmart AC/DC coupling
Add support for setting Sainsmart AC/DC coupling

uffejakobsen/sigrok-firmware-fx2lafw,uffejakobsen/sigrok-firmware-fx2lafw,swegener/sigrok-firmware-fx2lafw,uffejakobsen/sigrok-firmware-fx2lafw,swegener/sigrok-firmware-fx2lafw,swegener/sigrok-firmware-fx2lafw,uffejakobsen/sigrok-firmware-fx2lafw,swegener/sigrok-firmware-fx2lafw