Unable to set Set servo mission item for index bigger than 5

[Jaeyoung-Lim]

Expected Behavior

You should be able to use the "Set servo" mission item to configure servo outputs during a mission as configured in QGC mission plan

Current Behavior

QGC returns a error message that the servo index should be between 0...5
However, this doesn't make much sense, especially given that the servos are usually connected to higher index numbers

Steps to Reproduce:

Please provide an unambiguous set of steps to reproduce the current behavior

1. Add a Set servo mission item to the mission
2. Try to set a PWM value for servo 9
3. Upload mission to vehicle
4. QGC complains that the actuator index should be between 0-5

System Information

• Operating System: Ubuntu 18.04 Bionic
• QGC Version: 4.1.1
• QGC build: stable
• Flight Controller: PX4 SITL
• Autopilot (with version): PX4 master(22abe16)

Detailed Description

This was observed when trying to test PX4/PX4-Autopilot#16758

Log Files and Screenshots

[DonLakeFlyer]

That message is coming from the firmware. You'll need to talk with them.