libata-link: linkify reset

Make reset methods and related functions deal with ata_link instead of
ata_port.

* ata_do_reset()
* ata_eh_reset()
* all prereset/reset/postreset methods and related functions

This patch introduces no behavior change.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/pata_pdc2027x.c b/drivers/ata/pata_pdc2027x.c
index 83c90ca..ba39efb 100644
--- a/drivers/ata/pata_pdc2027x.c
+++ b/drivers/ata/pata_pdc2027x.c
@@ -300,7 +300,7 @@
 
 /**
  *	pdc2027x_prereset - prereset for PATA host controller
- *	@ap: Target port
+ *	@link: Target link
  *	@deadline: deadline jiffies for the operation
  *
  *	Probeinit including cable detection.
@@ -309,12 +309,12 @@
  *	None (inherited from caller).
  */
 
-static int pdc2027x_prereset(struct ata_port *ap, unsigned long deadline)
+static int pdc2027x_prereset(struct ata_link *link, unsigned long deadline)
 {
 	/* Check whether port enabled */
-	if (!pdc2027x_port_enabled(ap))
+	if (!pdc2027x_port_enabled(link->ap))
 		return -ENOENT;
-	return ata_std_prereset(ap, deadline);
+	return ata_std_prereset(link, deadline);
 }
 
 /**