multi-arch: POC running FCOS pipeline with VMs as jenkins workers

[dustymabe]

Some of us recently met to try to figure out steps forward for adding multi-arch builds to our pipeline. One of the steps was to try to run the pipline, but using VMs (not containers spun up via kubernetes) as the workers for our builds for architectures where we can't get an openshift cluster.

Let's investigate this option and perhaps enumerate the amount of work that needs to be done in order to make it achievable. For this POC we don't even need multi-arch hardware as the same level of abstraction should apply cleanly for x86_64, but we did agree to get an aarch64 VM from Fedora Infra for the POC, so we can use that too. I'll look at acquiring one from Fedora infra.

[ravanelli]

@dustymabe Just to let you know when you come back, I got 2 VMs for POWER as well to use in the CI. It is in a public networking, no issues with vpns and such 😎

[dustymabe]

The POC seems to be going well. We have an aarch64 node that we then use gangplank to connect to and execute builds.

We are now bumping the lockfiles for aarch64 using this POC:

• gangplank: additions to aid in FCOS AARCH64 building coreos-ci-lib#83
• bump-lockfile: rework to get aarch64 bumping fedora-coreos-pipeline#360

I'm going to mark the POC phase of this as complete and we'll use #262 for future status updates.