From: ChenXiaoSong <chenxiaosong@kylinos.cn>

`make htmldocs` reports the following warning:

  Documentation/trace/debugging.rst: WARNING: document isn't included \
    in any toctree

Fix it by adding debugging.rst to toctree.

Signed-off-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
---
 Documentation/trace/index.rst | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/trace/index.rst b/Documentation/trace/index.rst
index 0b300901fd75..2827292f8f34 100644
--- a/Documentation/trace/index.rst
+++ b/Documentation/trace/index.rst
@@ -36,3 +36,4 @@ Linux Tracing Technologies
    user_events
    rv/index
    hisi-ptt
+   debugging
-- 
2.34.1