libata-sff: ap->[last_]ctl are SFF specific

ap->[last_]ctl are specific to SFF controllers.  Put them inside
CONFIG_ATA_SFF and move initialization into ata_sff_port_init().
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

drivers/ata/libata-core.c

@@ -5634,10 +5634,8 @@ struct ata_port *ata_port_alloc(struct ata_host *host)
 	ap->pflags |= ATA_PFLAG_INITIALIZING;
 	ap->lock = &host->lock;
 	ap->print_id = -1;
-	ap->ctl = ATA_DEVCTL_OBS;
 	ap->host = host;
 	ap->dev = host->dev;
-	ap->last_ctl = 0xFF;
 
 #if defined(ATA_VERBOSE_DEBUG)
 	/* turn on all debugging levels */

drivers/ata/libata-sff.c

@@ -3074,6 +3074,8 @@ EXPORT_SYMBOL_GPL(ata_pci_bmdma_init);
  */
 void ata_sff_port_init(struct ata_port *ap)
 {
+	ap->ctl = ATA_DEVCTL_OBS;
+	ap->last_ctl = 0xFF;
 }
 
 int __init ata_sff_init(void)

include/linux/libata.h

@@ -721,10 +721,10 @@ struct ata_port {
 
 #ifdef CONFIG_ATA_SFF
 	struct ata_ioports	ioaddr;	/* ATA cmd/ctl/dma register blocks */
-#endif /* CONFIG_ATA_SFF */
-
 	u8			ctl;	/* cache of ATA control register */
 	u8			last_ctl;	/* Cache last written value */
+#endif /* CONFIG_ATA_SFF */
+
 	unsigned int		pio_mask;
 	unsigned int		mwdma_mask;
 	unsigned int		udma_mask;
@@ -1435,7 +1435,11 @@ static inline void ata_tf_init(struct ata_device *dev, struct ata_taskfile *tf)
 {
 	memset(tf, 0, sizeof(*tf));
 
+#ifdef CONFIG_ATA_SFF
 	tf->ctl = dev->link->ap->ctl;
+#else
+	tf->ctl = ATA_DEVCTL_OBS;
+#endif
 	if (dev->devno == 0)
 		tf->device = ATA_DEVICE_OBS;
 	else