bbctl: add proper USB PID to udev rules

Signed-off-by: Jeppe Ledet-Pedersen <jlp@satlab.org>
bbctl: add continuous transmit, list and csm commands

Signed-off-by: Jeppe Ledet-Pedersen <jlp@satlab.org>
firmware: use double buffered transmit

Signed-off-by: Jeppe Ledet-Pedersen <jlp@satlab.org>