[libvirt] [PATCH 1/3] Virtual network cleanup/bugfixes

The first two patches remedy a bug found by Stefan Berger in the new brAddInetInterface() function that resulted in the broadcast address not being properly set. This is a regression from previous releases, so it should be pushed prior to the upcoming release. The third patch improves the API for a couple of functions that were recently added, but does not change any behavior. I'd be happy pushing it now or after the release.