Account for fact that virDomainDeviceDefCopy() does an inactive copy

Account for fact that virDomainDeviceDefCopy() does an inactive copy

In a few places (e.g. device attach/detach/update) we are given a
device XML, parse it but then need a copy of parsed data so that
the original can be passed to function handling the request over
inactive XML and the copy is then passed to function handling the
operation over live XML. Note, both functions consume passed
device on success, hence the need for copy.

The problem is in combination of how the copy is obtained and
where is passed. The copy is done by calling
virDomainDeviceDefCopy() which does only inactive copy, i.e. no
live information is copied over (e.g. no aliases).

Then, this copy (inactive XML effectively) is passed to function
handling live part of the operation (e.g.
qemuDomainUpdateDeviceLive()) and the definition containing all
the juicy, live bits is passed to function handling inactive part
of the operation (e.g. qemuDomainUpdateDeviceConfig()).

This is rather incorrect, and XML copies should be passed to
their respective functions.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2036895
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Laine Stump <laine@redhat.com>