[libata] trim trailing whitespace

Most of these contributed by that mysterious figger known as A.C.

Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/ata/ata_piix.c

@@ -632,7 +632,7 @@ static int piix_pata_prereset(struct ata_port *ap)
 
 	if (!pci_test_config_bits(pdev, &piix_enable_bits[ap->port_no]))
 		return -ENOENT;
-		
+
 	ap->cbl = ATA_CBL_PATA40;
 	return ata_std_prereset(ap);
 }