fedora-common-ostree: Prepare for ppc64le support in bootupd

As bootupd supports GRUB and ppc64le since 0.2.10, we wil be able to
enable it once we enable bootupd support in Silverblue & friends.

See: https://github.com/coreos/bootupd/pull/420
See: https://fedoraproject.org/wiki/Changes/FedoraSilverblueBootupd

fedora-common-ostree.yaml

@@ -15,6 +15,7 @@ include: fedora-common-ostree-pkgs.yaml
 # arch-include:
 #   x86_64: bootupd.yaml
 #   aarch64: bootupd.yaml
+#   ppc64le: bootupd.yaml
 
 packages:
   # Ensure that we have a kernel. Kernel packages are not in any comps group