This reverts commit 903e051a71 to fix
<https://bugs.gnu.org/31365>. The full path of the 'ip' command is already
embedded, and we want to search 'qemu' in PATH.
* gnu/packages/virtualization.scm (libvirt): Remove 'wrap-libvirtd phase. Add
configure flags to run qemu as 'nobody:kvm'.
* gnu/services/virtualization.scm (libvirt-service-type): Add 'qemu' to the
system profile.