battery and heartbeat telemetry
parse VTX packets and VTX telemetry
provide GPS, Battery, Attitude, FlightMode telemetry
issue parameter updates at scheduled rate
support setting power levels with dbm
support standalone mode
set defaults from incoming VTX packets
output configured VTX settings
add support for temperature, battery voltage, battery current, flight pack
altitiude, airspeed, attitude and compass, GPS, ESC telemetry based on BLHeli
status messages and QOS packets.
refactor into AP_Telemetry
conditionally compile based on HAL_MINIMIZE_FEATURES
don't initialize spektrum telemetry if there is no RC uart