libata: kill ata_chk_status()

ata_chk_status() just calls ops->check_status and it only adds
confusion with other status functions.  Kill it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/ata/pata_bf54x.c

@@ -1264,7 +1264,7 @@ static void bfin_bmdma_freeze(struct ata_port *ap)
 	 * ATA_NIEN manipulation.  Also, many controllers fail to mask
 	 * previously pending IRQ on ATA_NIEN assertion.  Clear it.
 	 */
-	ata_chk_status(ap);
+	ap->ops->check_status(ap);
 
 	bfin_irq_clear(ap);
 }