openhorizon/ibm.hello-mms_ppc64le missing

[dlarson04]

Now that we are supporting ppc64le, it would be nice to have an openhorizon/ibm.hello-mms_ppc64le service accessible

[joewxboy]

@dabooz and @bmpotter there's a greater discussion that should happen (where?) about what architectures are officially supported, and what that means. In examples, does that mean that our non-functional, hello world type services should be available for all of these architectures? What does it mean for all pipelines? I don't mean to have that discussion in this thread, but this thread is what triggered it.