The QmpOutputVisitor has no direct dependency on QMP. It is
valid to use it anywhere that one wants a QObject. Rename it
to better reflect its functionality as a generic QAPI
to QObject converter.

The commit before previous renamed the files, this one renames C
identifiers.
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-Id: <1475246744-29302-6-git-send-email-berrange@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
[Split into file rename and identifier rename]
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>