Florian Bezdeka authored Mar 23, 2023 and Jan Kiszka committed Mar 23, 2023

Each branch (represented by the xenomai_<branch>.yml files) can now
define the latest kernel version that is supported by this branch. The
qemu build and test jobs will only be run for this kernel version.

Note: The stable/v3.0.x and stable/v3.1.x branches do not define a
latest kernel version. For those branches no qemu build and test jobs
will be scheduled. For stable/v3.0.x the situation is unchanged,
for stable/v3.1.x no qemu tasks will be scheduled anymore.

All qemu jobs can be re-enabled on pipeline creation time when the env
variale named ALL_QEMU_JOBS is set to "true". CI documentation has been
updated.

ALL_QEMU_JOBS and LAVA_TESTS_ENABLED might be feeded in by the gitlab UI
to limit the number of CI jobs.

We have to forward this variables to the downstream pipelines. Previously
they were defined with their default values in downstream pipelines which
made it impossible to overwrite the default from outside.

Signed-off-by: Florian...