ide: move ack_intr() method into 'struct ide_port_ops' (take 2)

Move the ack_intr() method into 'struct ide_port_ops', also renaming it to
test_irq() while at it...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
index 9e53efe..1059f80 100644
--- a/drivers/ide/ide-io.c
+++ b/drivers/ide/ide-io.c
@@ -804,7 +804,8 @@
 
 	spin_lock_irqsave(&hwif->lock, flags);
 
-	if (hwif->ack_intr && hwif->ack_intr(hwif) == 0)
+	if (hwif->port_ops && hwif->port_ops->test_irq &&
+	    hwif->port_ops->test_irq(hwif) == 0)
 		goto out;
 
 	handler = hwif->handler;