Change I79a8d8ac7ad2fbd7d2fce696821d130218e43e03 removed the install
of python-libguestfs, which was actually hiding a dependency issue on
Centos. The "kvm" package is ultimately missing some bios files from
"seabios-bin" -- however with python-libguestfs installed this was
coming in via a dependency chain that pulled in qemu-kvm, which has
the dependency.
qemu-kvm is not strictly required as all the functionality is within
qemu-system-x86. But while we get [1] sorted out this restores the
job functionality.
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1235890
Change-Id: I3379bc497978befac48c5af0f1035b96d030b7eb