Issues with disco-l475-iot1 boards in the LAVA Lab

[pfalcon]

Following issues with (apparent) flash wear-out with frdm-k64f boards in the Lab, there're now flashing issues with the disco-l475-iot1 boards there too: https://validation.linaro.org/scheduler/device_type/disco-l475-iot1 .

This ticket is created to triage these issues before reporting to the Lab.

[pfalcon]

The problems started on 2021-01-27 . The last clearly successful job from previous day is https://validation.linaro.org/scheduler/job/2320826

[pfalcon]

And the difference between last non-failing job and first failing job is LAVA version:

• https://validation.linaro.org/scheduler/job/2320826 - 2020.12
• https://validation.linaro.org/scheduler/job/2321501 - 2021.01

[pfalcon]

On the closer inspection, here're 2 successful healthjobs with 2021.01:

https://validation.linaro.org/scheduler/job/2321459 - lite-disco-l475-iot1-02
https://validation.linaro.org/scheduler/job/2321461 - lite-disco-l475-iot1-01

But next actual test job, https://validation.linaro.org/scheduler/job/2321501, started to fail, as well as most of the following.