[Feature Request]: Support hmc5883l & qmc5883l

[unbelauscht]

Platform

ESP32

Description

Supporting hmc5883l & qmc5883l modules would provide accurate compass data for heading vs buggy GPS calculated heading.

EDIT: I can find hmc & qmc mentions in the code, but it's not clear how to attach a module and how to enable it.

[garethhcoleman]

I can see that QMC5883L has some mentions in the code as a telemetry sensor but it isn't coded in a telemetry module or listed as supported here. Recently @caveman99 made this comment about telemetry for an accelerometer that I think is relevant to your request "We only support slow-changing data or data with is averaged over time. Use cases for this type of sensor is heading while stationary (add-on to position module)".

[fifieldt]

@dhskinner is working on accelerometer support which should be helpful for compasses
meshtastic/firmware#4662

for now, a QMC5883L will be detected if plugged in by I2C, but nothing much will happen with it.