event-test: Check for virConnectRegisterCloseCallback return value
event-test: Check for virConnectRegisterCloseCallback return value

In an unlikely event of virConnectRegisterCloseCallback failing,
the error is ignored. This is an example file and we shouldn't
get a bad example.

Signed-off-by: Michal Privoznik <83d82aaba2eed257f4814b0c239c260c4caaadf0@redhat.com>

taget/libvirt,jardasgit/libvirt,taget/libvirt,andreabolognani/libvirt,taget/libvirt,jfehlig/libvirt,eskultety/libvirt,datto/libvirt,taget/libvirt,eskultety/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,crobinso/libvirt,olafhering/libvirt,eskultety/libvirt,olafhering/libvirt,eskultety/libvirt,VenkatDatta/libvirt,nertpinx/libvirt,eskultety/libvirt,libvirt/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,crobinso/libvirt,andreabolognani/libvirt,VenkatDatta/libvirt,zippy2/libvirt,nertpinx/libvirt,andreabolognani/libvirt,jardasgit/libvirt,zippy2/libvirt,fabianfreyer/libvirt,fabianfreyer/libvirt,datto/libvirt,nertpinx/libvirt,libvirt/libvirt,fabianfreyer/libvirt,taget/libvirt,zippy2/libvirt,libvirt/libvirt,libvirt/libvirt,jfehlig/libvirt,olafhering/libvirt,nertpinx/libvirt,zippy2/libvirt,andreabolognani/libvirt,olafhering/libvirt,jfehlig/libvirt,crobinso/libvirt,datto/libvirt,VenkatDatta/libvirt,andreabolognani/libvirt,nertpinx/libvirt,crobinso/libvirt,datto/libvirt,datto/libvirt,jfehlig/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,VenkatDatta/libvirt