[libvirt] Enabling libvirt admin API

[Erik Skultety]

It's been a while since an RFE for getting and setting specific daemon
configuration parameters[1] during runtime landed in bugzilla. Although
there was only need for dynamic reconfiguration of number of connected
clients allowed in the original request, the plan Dan proposed was to
implement a separate libvirt administration library, specifying some
ideas regarding the functionality that the first version should support.
These of course needed a fair amount of helper functions (before any API
could be introduced), so a decision to explicitly disable creation of
the admin socket (also neither distributing the .so nor the header)
until the interface is capable to do something more than just
connecting/disconnecting, listing servers and polling for library
version has been made.
Besides the dynamic reconfiguration of the logging parameters which has
been waiting in the list (presumably needs a fresh rebase onto the
current master) due to being related and dependent on the logging level
refactor[2] (I CCed Daniel as he might have an update on this), the
remaining requirements on the interface have been met already. So I was
wondering if we could manage to enable it in the upcoming release, as
well as getting it to 7.3 (thus not delaying the RFC anymore). I'd like
to hear your opinions on this matter, possibly because I might have
missed something that would cause the "official" release of the feature
to be prolonged even more.

[1] https://bugzilla.redhat.com/show_bug.cgi?id=735385
[2] https://www.redhat.com/archives/libvir-list/2016-May/msg00760.html

Regards,
Erik