libata-scsi passthru: fix bug which truncated LBA48 return values

Fix assignment which overwrote SAT ATA PASS-THROUGH command EXTEND
bit setting (ATA_TFLAG_LBA48)
Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/libata-scsi.c

@@ -2875,7 +2875,7 @@ static unsigned int ata_scsi_pass_thru(struct ata_queued_cmd *qc)
 	 * write indication (used for PIO/DMA setup), result TF is
 	 * copied back and we don't whine too much about its failure.
 	 */
-	tf->flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
 	if (scmd->sc_data_direction == DMA_TO_DEVICE)
 		tf->flags |= ATA_TFLAG_WRITE;