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: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 19f716e..85b99b8 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -721,10 +721,10 @@
 
 #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 @@
 {
 	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