Add the USB identification of the dcttech.com USBRelay<n> card. Which
happens to be shared with other V-USB based firmware projects. Thus is
rather generic. The USB relay card is just the first supported device
of that kind.
# Dangerous Prototypes Buspirate (v4)
ATTRS{idVendor}=="04d8", ATTRS{idProduct}=="fb00", ENV{ID_SIGROK}="1"
+# dcttech.com USB relay card, and other V-USB based firmware
+ATTRS{idVendor}=="16c0", ATTRS{idProduct}=="05df", ENV{ID_SIGROK}="1"
+
# DreamSourceLab DSLogic
ATTRS{idVendor}=="2a0e", ATTRS{idProduct}=="0001", ENV{ID_SIGROK}="1"
# DreamSourceLab DSLogic Pro