I don't see a good reason why we need anything but qemu-kvm.
The following commit adds the requirement - but I don't see the real need for it:
commit a7d71ad2994aab3234371e850c617b826b3681b1
Author: Rafael Martins <rmartins@redhat.com>
Date:   Tue Jan 3 15:26:54 2017 +0100

    Force usage of qemu-kvm-rhev on centos/rhel

    Lago requires qemu-kvm >= 2.1.2, these are the required
    package names for each distro:

    CentOS: the package is named 'qemu-kvm-ev', but it provides
    RHEL: named 'qemu-kvm-rhev'
    Fedora: 'qemu-kvm'

    Signed-off-by: gbenhaim <galbh2@gmail.com>
    Signed-off-by: Nadav Goldin <ngoldin@redhat.com>