Observation: RTT_LOGGING and Bluetooth interference

[SvenHaedrich]

I observed a total cease of operation under the following circumstances:

• ZMK_RTT_LOGGING enabled
• keyboard connected via Bluetooth

The keyboard worked fine for some 10 seconds, then it transmitted a "stucked" keystroke multiple times and finally stopped operation. This happens no matter if the actual connection is via USB or Bluetooth. With ZMK_RTT_LOGGING disabled, everything works fine. Also, if no Bluetooth connection is active. Or, if a debug probe fetches the RTT buffer. Obviously, something is going on with the RTT buffer, or the default settings for RTT.