Add support for s390x qemu

[okurz]

For now our tests on s390x only expected z/VM or KVM on s390x using the
svirt backend.

This commit now adds support for the third case using the (default) qemu
backend where we actually do not need to do anything s390x specific.

Verification runs:

for i in  https://openqa.suse.de/tests/14068509 https://openqa.opensuse.org/tests/4054629 https://openqa.opensuse.org/tests/4054622 https://openqa.suse.de/tests/14005042 https://openqa.suse.de/tests/14096877 https://openqa.suse.de/tests/14092754; do openqa-clone-custom-git-refspec https://github.com/os-autoinst/os-autoinst-distri-opensuse/pull/19128 $i; done

• sle-15-SP6-Online-s390x-Build79.1-okurz-poo158985-default-okurz-poo158985@s390x-kvm -> https://openqa.suse.de/tests/14103628 (so far expected to fail, native s390x qemu in development)
• opensuse-Tumbleweed-DVD-s390x-Build20240329-autoyast_zvm@s390x-zVM-vswitch-l2 -> https://openqa.opensuse.org/tests/4097728 (schedule as expected, fails later due to other reason)
• opensuse-Tumbleweed-DVD-s390x-Build20240329-textmode@s390x-zVM-vswitch-l2 -> https://openqa.opensuse.org/tests/4097729 (passed)
• sle-15-SP6-Online-s390x-Build79.1-default@s390x-kvm -> https://openqa.suse.de/tests/14105090 (passed)
• sle-15-SP6-Online-s390x-Build82.1-default@s390x-kvm -> https://openqa.suse.de/tests/14103626 (passed)
• sle-15-SP6-Online-s390x-Build82.1-default@s390x-zVM -> https://openqa.suse.de/tests/14103627 (passed)

But multiple fail due to https://progress.opensuse.org/issues/158170 which we need to sort out first.

Related progress issue: https://progress.opensuse.org/issues/158985

[github-actions]

Great PR! Please pay attention to the following items before merging:

Files matching lib/**.pm:

• Consider adding or extending unit tests in t/

This is an automatically generated QA checklist based on modified files.

[foursixnine]

For now our tests on s390x only expected z/VM or KVM on s390x using the svirt backend.

This commit now adds support for the third case using the (default) qemu backend where we actually do not need to do anything s390x specific.

Related progress issue: https://progress.opensuse.org/issues/158985

can you link to a verification run on the PR?

[okurz]

can you link to a verification run on the PR?

sure. please see the updated description #19128 (comment)