Description of problem:
virt-manager doesn't seem to be used for anything in /virt/install test and it's causing trouble for RHEL7 powerppc, because this package is not going to be shipped as part of RHEL. It pulls in couple other packages, which also are not going to be shipped with RHEL.

It seems this dependency can be removed entirely, as test is not interacting with virt-manager in any way. Furthermore it appears as redundant, at least on RHEL7, where @virtualization-client package group contains it as well:

Removing it from Makefile allows powerpc to use virt-manager repo (to install virt-install) and at the same time it doesn't pull in virt-manager and its dependencies.

Group: Virtualization Client
 Group-Id: virtualization-client
 Description: Clients for installing and managing virtualization instances.
 Mandatory Packages:
    gnome-boxes
    virt-install
    virt-manager
    virt-viewer
 Default Packages:
    virt-top
 Optional Packages:
   libguestfs-tools
   libguestfs-tools-c

Proposed patch:
        @echo "Requires:        mkisofs" >> $(METADATA)
        @echo "Requires:        openssh-server" >> $(METADATA)
        @echo "Requires:        python-virtinst" >> $(METADATA)
-       @echo "Requires:        virt-manager" >> $(METADATA)
        @echo "Requires:        virt-viewer" >> $(METADATA)
        @echo "Requires:        virt-install" >> $(METADATA)
        @echo "Requires:        vnc" >> $(METADATA)