There's nothing like "primary" architectures in Fedora.

There are currently those architectures:
armv7hl i686 x86_64 aarch64 ppc64le s390x

In Copr, we already have all except for s390x. armv7hl is already there, but
emulated, and we can provide the same for s390x. @schlupov is working on this.

Also note that we ATM don't build against ppc64le only temporarily:
https://pagure.io/fedora-infrastructure/issue/9059

ATM we support all the architectures, except for ppc64le where we are waiting for
the wiring of boxes in Fedora datacenter.

We support ppc64le again. I think we can close this one as done.