[libata] export ata_dev_pair; trim trailing whitespace

Mostly, trim trailing whitespace.

Also:
* export ata_dev_pair
* move ata_dev_classify export closer to ata_dev_pair export

drivers/scsi/libata-bmdma.c

@@ -941,7 +941,7 @@ err_out:
  *	@pdev: PCI device
  *
  *	Some PCI ATA devices report simplex mode but in fact can be told to
- *	enter non simplex mode. This implements the neccessary logic to 
+ *	enter non simplex mode. This implements the neccessary logic to
  *	perform the task on such devices. Calling it on other devices will
  *	have -undefined- behaviour.
  */
@@ -966,7 +966,7 @@ unsigned long ata_pci_default_filter(const struct ata_port *ap, struct ata_devic
 {
 	/* Filter out DMA modes if the device has been configured by
 	   the BIOS as PIO only */
-	   
+
 	if (ap->ioaddr.bmdma_addr == 0)
 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
 	return xfer_mask;