DOC: config: fix "Address formats" chapter syntax

The section on "Address formats" doesn't provide the dot (.) after the
chapter numbers, which breaks parsing within the HTML converter.
This commit adds the dot (.) after each chapter within Section 11.

This should be backported to versions 2.4 and above.

(cherry picked from commit 86aac23e6b5f8efde8950573705f494642c11f82)
Signed-off-by: Willy Tarreau <w@1wt.eu>
(cherry picked from commit a6538d3e628cef042905c8f631995ba387072045)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit f070489425dc2f7f21eb99eab22c92711cbe89fd)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit 28bd821247ae0f55c1e955c206f1746fe17f5306)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 04acab7..e1e0d50 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -22151,8 +22151,8 @@
 socket type and the transport method.
 
 
-11.1 Address family prefixes
-----------------------------
+11.1. Address family prefixes
+-----------------------------
 
 'abns@<name>' following <name> is an abstract namespace (Linux only).
 
@@ -22187,8 +22187,8 @@
                start by slash '/'.
 
 
-11.2 Socket type prefixes
--------------------------
+11.2. Socket type prefixes
+--------------------------
 
 Previous "Address family prefixes" can also be prefixed to force the socket
 type and the transport method. The default depends of the statement using
@@ -22210,8 +22210,8 @@
                             to "datagram".
 
 
-11.3 Protocol prefixes
-----------------------
+11.3. Protocol prefixes
+-----------------------
 
 'tcp@<address>[:port1[-port2]]' following <address> is considered as an IPv4
                                 or IPv6 address depending of the syntax but