ci-package-builder: Handle linux package's special needs

To properly handle the linux package build, the debian/control file needs to be re-generated on the fly to reflect our customizations like disabling some build flavors.

So far it shipped a custom pipeline, but that's problematic as it can go out of sync as it indeed did with the recent changes in this repository, yielding errors due to the sequence having changed, stages no longer matching, and artifacts being saved in different locations.

See also https://gitlab.apertis.org/pkg/target/linux/-/merge_requests/35