qemu-kvm-ev & related deps is part of CentOS virt SIG deliverables. We should not duplicate it ourselves, rather we should depend on CentOS repos.
Similarly for Fedora and virt-preview, I guess.
# grep -A4 qemu /etc/yum.repos.d/ovirt-4.2-pre-dependencies.repo
name=CentOS-7 - QEMU EV
This bugzilla is included in oVirt 4.2.0 release, published on Dec 20th 2017.
Since the problem described in this bug report should be
resolved in oVirt 4.2.0 release, published on Dec 20th 2017, it has been closed with a resolution of CURRENT RELEASE.
If the solution does not work for you, please open a new bug report.