twister: regression : Failures are counted as errors

[tpennors]

Describe the bug
Failures are counted as errors. Must be a regression because it was working well before

To Reproduce
Steps to reproduce the behavior:

1. Create a build error in zephyr/samples/hello_world/main.c
2. run ./scripts/twister -T samples/hello_world/ -p b_u585i_iot02a
3. See error:
   

Impact
The big problem is that as failure and error are inverted, twister return code is not 1 when failure occurs so CI does not pass in failure. As it can be seen in twister script:

if results.failed or (tplan.warnings and options.warnings_as_errors):
        sys.exit(1)

Environment (please complete the following information):

• OS: OS: ubuntu 20.04
• Toolchain zephyr-sdk 0.13.1
• Commit SHA or Version : v3.1.0 TAG

[nashif]

backport fix available, this is 3.1 specific.

[nashif]

#47703 merged