iscsi: Assign bs to file in iscsi_co_get_block_status

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1453780743-16806-6-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

block/iscsi.c

@@ -625,6 +625,9 @@ out:
     if (iTask.task != NULL) {
         scsi_free_scsi_task(iTask.task);
     }
+    if (ret > 0 && ret & BDRV_BLOCK_OFFSET_VALID) {
+        *file = bs;
+    }
     return ret;
 }