s390/qdio: eliminate queue's last_move cursor

This cursor is used for debugging only. But since
commit "s390/qdio: pass up count of ready-to-process SBALs" it effectively
duplicates the first_to_check cursor, diverging for just a short moment
when get_*_buffer_frontier() updates q->first_to_check.

Signed-off-by: Julian Wiedmann <[e-mail]>
Reviewed-by: Jens Remus <[e-mail]>
Signed-off-by: Martin Schwidefsky <[e-mail]>

drivers/s390/cio/qdio.h

···
 	 */
 	int first_to_check;
 
-	/* first_to_check of the last time */
-	int last_move;
-
 	/* beginning position for calling the program */
 	int first_to_kick;
 

drivers/s390/cio/qdio_debug.c

···
 
 	seq_printf(m, "Timestamp: %Lx  Last AI: %Lx\n",
 		   q->timestamp, last_ai_time);
-	seq_printf(m, "nr_used: %d  ftc: %d  last_move: %d\n",
-		   atomic_read(&q->nr_buf_used),
-		   q->first_to_check, q->last_move);
+	seq_printf(m, "nr_used: %d  ftc: %d\n",
+		   atomic_read(&q->nr_buf_used), q->first_to_check);
 	if (q->is_input_q) {
 		seq_printf(m, "polling: %d  ack start: %d  ack count: %d\n",
 			   q->u.in.polling, q->u.in.ack_start,

drivers/s390/cio/qdio_main.c

···
 
 	count = get_inbound_buffer_frontier(q);
 
-	if (count) {
-		q->last_move = q->first_to_check;
-		if (!is_thinint_irq(q->irq_ptr) && MACHINE_IS_LPAR)
-			q->u.in.timestamp = get_tod_clock();
-	}
+	if (count && !is_thinint_irq(q->irq_ptr) && MACHINE_IS_LPAR)
+		q->u.in.timestamp = get_tod_clock();
 
 	return count;
 }
···
 
 	count = get_outbound_buffer_frontier(q);
 
-	if (count) {
-		q->last_move = q->first_to_check;
+	if (count)
 		DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out moved:%1d", q->nr);
-	}
 
 	return count;
 }