Introduce new error label to avoid the unnecessary checking of net
pointer.
Fixes: 1e0a84ea49b68 ("vhost-vdpa: introduce vhost-vdpa net client")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20210903091031.47303-10-jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>