libata-sff: rename ap->ops->drain_fifo() to sff_drain_fifo()

->drain_fifo() is SFF specific.  Rename and relocate it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/pata_pcmcia.c b/drivers/ata/pata_pcmcia.c
index d94b8f0..ef37438 100644
--- a/drivers/ata/pata_pcmcia.c
+++ b/drivers/ata/pata_pcmcia.c
@@ -175,7 +175,7 @@
 	.sff_data_xfer	= ata_data_xfer_8bit,
 	.cable_detect	= ata_cable_40wire,
 	.set_mode	= pcmcia_set_mode_8bit,
-	.drain_fifo	= pcmcia_8bit_drain_fifo,
+	.sff_drain_fifo	= pcmcia_8bit_drain_fifo,
 };