Fix a major brain-o. If the command needs to be put on the deferred queue,

take it off of the busy queue first.  This should fix the 'command is on
another queue' panic that showed up recently.

sys/dev/aac/aac.c

@@ -1290,6 +1290,7 @@ aac_map_command_sg(void *arg, bus_dma_segment_t *segs, int nseg, int error)
 
 	/* put the FIB on the outbound queue */
 	if (aac_enqueue_fib(sc, cm->cm_queue, cm) == EBUSY) {
+		aac_remove_busy(cm);
 		aac_unmap_command(cm);
 		aac_requeue_ready(cm);
 	}