Decide what to do with ppc64le support
Context
Current ppc64le builder is inoperative. We either need to get builder back up or drop the architecture. Once 21.08 release is done, ppc64le will become an outlier which cannot be built with previous release's PreBootstrap image. We also don't have a functioning Docker image for the architecture anymore.
Description
Either get a builder or remove support from master completely.
Acceptance Criteria
There is a resolution to ppc64le problem
Edited by Seppo Yli-Olli