IBUS telemetry enabled discconects fs-ia6b

When using ibus telemetry with a fs-ia6b the RX will disconnect after a short period of time. If using a fs-ia10b it will not disconnect. Have noticed this on various FCs.

## Bug report

**Issue details**

_Please describe the problem_

**Version**
_What version was the issue encountered with_

**Platform**
[ ] All
[ ] AntennaTracker
[ x ] Copter
[ ] Plane
[ ] Rover
[ ] Submarine

**Airframe type**
_What type of airframe (flying wing, glider, hex, Y6, octa etc)_
Heli

**Hardware type**
_What autopilot hardware was used? (Pixhawk, Cube, Pixracer, Navio2, etc)_
mini-pix, AtomRCF405
**Logs**
_Please provide a link to any relevant logs that show the issue_

Start by reproducing the IBUS telemetry disconnect with an fs-ia6b, comparing it with an fs-ia10b on the listed flight controllers. Review the available issue details and collect the missing version and logs; done means the RX remains connected during IBUS telemetry use without regressing the fs-ia10b case.

Written by the indexing model from the issue text.