feature request: telemetry output in FlySky iBUS format

[cbf123]

Just wondering whether we could get the option of sending the telemetry in the FlySky iBUS format as an alternative to S.Port. The FS-iA6B and FS-iA10B are excellent low-cost receivers that can return telemetry. With an OpenTX radio the options for telemetry are much expanded.

See https://github.com/betaflight/betaflight/wiki/Single-wire-FlySky-(IBus)-telemetry for protocol info, and https://github.com/opentx/opentx/blob/2.3/radio/src/telemetry/flysky_ibus.cpp for OpenTX iBUS sensors.

[sskaug]

At the moment we have no plans for this. This is not in line with the primary application area for BLHeli (which is multirotors) and also memory is starting to become full for 32kB flash ESCs.