pua_dialoginfo: docs for attribute_display param

src/modules/pua_dialoginfo/doc/pua_dialoginfo_admin.xml

@@ -601,6 +601,26 @@ modparam("pua_dialoginfo", "publish_dialog_req_within", 0)
 			</programlisting>
                 </example>
                 </section>
+
+        <section id="pua_dialoginfo.p.attribute_display">
+            <title><varname>attribute_display</varname> (int)</title>
+            <para>
+            If set to 1, the display name attribute is added with user part of the
+            URI for local and remote targets.
+            </para>
+            <para>
+                <emphasis>Default value is <quote>0</quote>.</emphasis>
+            </para>
+            <example>
+                <title>Set <varname>attribute_display</varname> parameter</title>
+                <programlisting format="linespecific">
+...
+modparam("pua_dialoginfo", "attribute_display", 1)
+...
+</programlisting>
+            </example>
+        </section>
+
     </section>
 
 	<section>