Requires https://github.com/airspy/host
Usage example:
osmocom_fft -a airspy
The following named gain stages are available:
LNA: 0 to 15, step 1
MIX: 0 to 15, step 1
IF: 0 to 15, step 1
At the moment the gains are not in dB but gain indices internal to R820t
tuner.
