This will be needed by vhost-user-test, when each test switches to
its own GMainLoop and GMainContext.  Otherwise, for a reconnecting
socket the initial connection will happen on the default GMainContext,
and no one will be listening on it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20190202110834.24880-1-pbonzini@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>