Px4-autopilot: Datalink lost with termination enabled leads to termination

[julianoes]

According to https://discuss.px4.io/t/px4-mission-mode-crash/10847/2 it looks like flight termination is triggered if datalink is lost and we're in mission mode even if GPS and RC are ok.

The message in this case says: "DL and GPS lost: flight termination".

https://github.com/PX4/Firmware/blob/7ec6f0dca6ec604e5a62707e487ad754a23ded7a/src/modules/commander/Commander.cpp#L2231-L2242

FYI: @LorenzMeier @dagar

[bresch]

This will be fixed in PR #10179 here: https://github.com/PX4/Firmware/pull/10179/commits/57b527778f9bf3c3ba6bd9df81f9eb6ee6ea65c7

[dagar]

We need a minimal fix for v1.9.0.

[julianoes]

@bresch can you make a PR with just 57b5277, I think that's covering it for 1.9.0.