add missing @ in comment

Signed-off-by: npes87184 <npes87184@gmail.com>
---
 include/block/block_int.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/block/block_int.h b/include/block/block_int.h
index 903b9c1034..2ce016ea94 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -221,7 +221,7 @@ struct BlockDriver {
                                                 BdrvRequestFlags read_flags,
                                                 BdrvRequestFlags write_flags);
 
-    /* Map [offset, offset + nbytes) range onto a child of bs to copy data to,
+    /* Map [offset, offset + nbytes) range onto a child of @bs to copy data to,
      * and invoke bdrv_co_copy_range_to(child, src, ...), or perform the copy
      * operation if @bs is the leaf and @src has the same BlockDriver.  Return
      * -ENOTSUP if @bs is the leaf but @src has a different BlockDriver.
-- 
2.17.1