wireshark dissector for CBSP protocol
wireshark doesn't yet have a CBSP dissector for the protocol between CBC and BSC. Let's add it.
Initial code is found at https://git.osmocom.org/wireshark/log/?h=laforge/cbsp
Some feedback at https://code.wireshark.org/review/#/c/29745/
Sample capture from real network at https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=15143