Support s390x arch

[carlcsaposs-canonical]

Summary

Add support for the s390x architecture

Why is this important?

Test s390x Kubernetes charms

We're adding s390x support to the MySQL charms in order to support Sunbeam on s390x (https://warthogs.atlassian.net/browse/DPE-7054). cc @paulomach

Currently, we're using microk8s (from edge) to test the Kubernetes charms on s390x. However, the strict microk8s snap is incompatible with a Hardware Enablement kernel, which is used on Canonical's IS-hosted GitHub runners (details: https://chat.canonical.com/canonical/pl/i6yydsx5ifrepp56khq5fq5dke)

We were recommended to use Canonical Kubernetes instead of microk8s (https://chat.canonical.com/canonical/pl/akysf8unw7gjfqbbidcghjf4so), but Canonical Kubernetes does not currently support s390x

Are you interested in contributing to this feature?

Happy to help, but don't think we can implement this ourselves

[HomayoonAlimohammadi]

Hi @carlcsaposs-canonical and thank you for opening this issue. I believe we've asked for a PF card internally and expect to have it in the cycles to come. If this needs escalation or more attention, please let us know either here or through internal communication channels.