Devices that are running at splimp MUST use ng_queue_data()

instead of ng_send_data().
The latter could lead to running the IP stack at splimp
instead of splnet, (among other problems) (that MAY be safe
but I wouldn't count on it).

Noticed while preparing a new set of netgraph stuff.

sys/dev/lmc/if_lmc.c

@@ -625,8 +625,7 @@ lmc_rx_intr(lmc_softc_t * const sc)
 			if (accept) {
 				ms->m_pkthdr.len = total_len;
 				ms->m_pkthdr.rcvif = NULL;
-				ng_send_data(sc->lmc_hook,
-				    ms, NULL, NULL, NULL);
+				ng_queue_data(sc->lmc_hook, ms, NULL);
 			}
 			ms = m0;
 		}