Possibly roll back change blocking fast RFM channels.
Currently an IPCx part with an RFM (long range) type in a model with ipc_rate > 16 will cause an RCG error.
Fast RFM channels are downsampled to 16k automatically by the RFM. There is still a problem of the 4km delay. Since the delay of 65k IPCs is only 16 us, there isn't enough time for the IPC value to get to the end station.
We should also consider higher values for rfm_delay so fast data has time to get to the end. See #502 (closed).
Possibly consider an RCG warning if ipc_rate is high and rfm_delay is low.