Constant preflight fail log messages about not being connected to ground station

[chris1seto]

Describe the bug

In head of main px4, (~ 9159f02) there is constant log spam about not being connected to a ground station. While it might be common to be connected to a ground station, it's not required. I think this error message could better be used if it appears only once after a previously connected ground station disconnects.

Alternative solutions

• A param bitfield which can be used to select which preflight checks were desired to be checked
• Only checking for preflight/health issues during actual arming, and otherwise staying silent if the vehicle is in prearm or idle (not armed or prearmed)

To Reproduce

Steps to reproduce the behavior:

1. Power on Px4 without ground station connected
2. Log messages of the form WARN [health_and_arming_checks] Preflight Fail: No connection to the ground control station will be continuously printed

Log

https://review.px4.io/plot_app?log=d2984592-304c-46f8-94c4-9222392b2228

[bkueng]

Yes some of these are a bit spamming at the moment. But note that we'll completely remove these mavlink_log's once the GCS has the events UI in a release.
For now I'm fine with reducing the verbosity a bit. Do you want to do a PR?

[abdulmelikbekmez]

You can use this parameter to avoid these situations.