libata: use the WRITE_SAME_16 define

Now that the scsi tree has hit mainline we can use the newly added WRITE_SAME_16
define.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 1683ebd..f4ea5a8 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -3022,7 +3022,7 @@
 	case WRITE_16:
 		return ata_scsi_rw_xlat;
 
-	case 0x93 /*WRITE_SAME_16*/:
+	case WRITE_SAME_16:
 		return ata_scsi_write_same_xlat;
 
 	case SYNCHRONIZE_CACHE: