Some time ago, _libvirt_ was refactored to use separate daemons and
sockets for each of its responsibilities, and the original "monolithic"
`libvirtd` was made obsolete. The Fedora packages have more recently
been adjusted to favor this new approach, and now default to omitting
the monolithic daemon entirely (when `install_weak_deps` is disabled).
One interesting packaging snafu, though, is that without the weak
dependencies, there is _no_ way for clients to connect by default.
Clients run `which virt-ssh-helper` to see if it is installed, which it
is, but `which` is not. They then fall back to running `nc`, which is
_also_ not installed. So even though the tools they actually need are
present, their logic for detecting this is broken. As such, we need to
explicitly install `which` to satisfy them.