Documentation: add note block surrounding security patch note

Security patches have different handling than rest of patches for
review.

Enclose note paragraph about such patches in `.. note::` block.

Cc: Sasha Levin <sashal@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20220314113329.485372-2-bagasdotme@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/process/stable-kernel-rules.rst

@@ -35,7 +35,9 @@ Rules on what kind of patches are accepted, and which ones are not, into the
 Procedure for submitting patches to the -stable tree
 ----------------------------------------------------
 
- - Security patches should not be handled (solely) by the -stable review
+.. note::
+
+   Security patches should not be handled (solely) by the -stable review
    process but should follow the procedures in
    :ref:`Documentation/admin-guide/security-bugs.rst <securitybugs>`.