RSSI channel not being saved - old issue, still present

[nerdCopter]

emuflight/EmuFlight#460

Describe the bug
RSSI channel is not being saved (CLI and GUI - same thing).
There is some workaround (rssi_adc should be off in a first place), but it is not a proper fix I think.

To Reproduce
as in this video:
https://www.youtube.com/watch?v=x-qdaVpmn5o

Expected behavior
RSSI channel should be saved but it is not.

Additional context
It is old issue with a known workaround but it should not behave like this anyways - I think.