docs: clearing-warn-once.txt: add a title for this document

This document misses a title. Add it, in order to follow
the documentation standard.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/Documentation/clearing-warn-once.txt b/Documentation/clearing-warn-once.txt
index 5b1f5d547be1..4aa938262d0e 100644
--- a/Documentation/clearing-warn-once.txt
+++ b/Documentation/clearing-warn-once.txt
@@ -1,3 +1,5 @@
+Clearing WARN_ONCE
+------------------
 
 WARN_ONCE / WARN_ON_ONCE only print a warning once.