xenconfig: Resolve Coverity RESOURCE_LEAK
xenconfig: Resolve Coverity RESOURCE_LEAK

Since '337a13628' - Coverity complains that 'net' is VIR_ALLOC()'d, but
on various 'cleanup' exit paths from the code there is no corresponding
cleanup.

datto/libvirt,VenkatDatta/libvirt,taget/libvirt,datto/libvirt,olafhering/libvirt,elmarco/libvirt,nertpinx/libvirt,eskultety/libvirt,olafhering/libvirt,VenkatDatta/libvirt,shugaoye/libvirt,rlaager/libvirt,jfehlig/libvirt,jfehlig/libvirt,VenkatDatta/libvirt,shugaoye/libvirt,jfehlig/libvirt,libvirt/libvirt,shugaoye/libvirt,fabianfreyer/libvirt,libvirt/libvirt,rlaager/libvirt,rlaager/libvirt,olafhering/libvirt,eskultety/libvirt,fabianfreyer/libvirt,taget/libvirt,nertpinx/libvirt,nertpinx/libvirt,elmarco/libvirt,datto/libvirt,andreabolognani/libvirt,rlaager/libvirt,shugaoye/libvirt,elmarco/libvirt,crobinso/libvirt,agx/libvirt,zippy2/libvirt,andreabolognani/libvirt,eskultety/libvirt,nertpinx/libvirt,elmarco/libvirt,agx/libvirt,rlaager/libvirt,crobinso/libvirt,shugaoye/libvirt,VenkatDatta/libvirt,nertpinx/libvirt,andreabolognani/libvirt,agx/libvirt,taget/libvirt,crobinso/libvirt,eskultety/libvirt,zippy2/libvirt,jardasgit/libvirt,eskultety/libvirt,jardasgit/libvirt,datto/libvirt,datto/libvirt,crobinso/libvirt,zippy2/libvirt,taget/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,jfehlig/libvirt,libvirt/libvirt,taget/libvirt,zippy2/libvirt,fabianfreyer/libvirt,andreabolognani/libvirt,olafhering/libvirt,jardasgit/libvirt,fabianfreyer/libvirt,libvirt/libvirt,andreabolognani/libvirt,jardasgit/libvirt,VenkatDatta/libvirt,agx/libvirt,agx/libvirt,elmarco/libvirt