dialog fix typo in README and doc

The call_id_column variable was named callid_column in the doc.

modules/dialog/README

@@ -56,7 +56,7 @@ Alex Balashov
               5.13. db_fetch_rows (integer)
               5.14. db_skip_load (integer)
               5.15. table_name (string)
-              5.16. callid_column (string)
+              5.16. call_id_column (string)
               5.17. from_uri_column (string)
               5.18. from_tag_column (string)
               5.19. to_uri_column (string)
@@ -271,7 +271,7 @@ Chapter 1. Admin Guide
         5.13. db_fetch_rows (integer)
         5.14. db_skip_load (integer)
         5.15. table_name (string)
-        5.16. callid_column (string)
+        5.16. call_id_column (string)
         5.17. from_uri_column (string)
         5.18. from_tag_column (string)
         5.19. to_uri_column (string)
@@ -477,7 +477,7 @@ Chapter 1. Admin Guide
    5.13. db_fetch_rows (integer)
    5.14. db_skip_load (integer)
    5.15. table_name (string)
-   5.16. callid_column (string)
+   5.16. call_id_column (string)
    5.17. from_uri_column (string)
    5.18. from_tag_column (string)
    5.19. to_uri_column (string)
@@ -744,15 +744,15 @@ modparam("dialog", "db_skip_load", 1)
 modparam("dialog", "table_name", "my_dialog")
 ...
 
-5.16. callid_column (string)
+5.16. call_id_column (string)
 
    The column name in the database to store the dialogs' callid.
 
    Default value is "callid".
 
    Example 1.16. Set callid_column parameter
 ...
-modparam("dialog", "callid_column", "callid_c_name")
+modparam("dialog", "call_id_column", "callid_c_name")
 ...
 
 5.17. from_uri_column (string)

modules/dialog/doc/dialog_admin.xml

@@ -533,7 +533,7 @@ modparam("dialog", "table_name", "my_dialog")
 	</section>
 
 	<section>
-		<title><varname>callid_column</varname> (string)</title>
+		<title><varname>call_id_column</varname> (string)</title>
 		<para>
 			The column name in the database to store the dialogs' callid.
 		</para>
@@ -546,7 +546,7 @@ modparam("dialog", "table_name", "my_dialog")
 		<title>Set <varname>callid_column</varname> parameter</title>
 		<programlisting format="linespecific">
 ...
-modparam("dialog", "callid_column", "callid_c_name")
+modparam("dialog", "call_id_column", "callid_c_name")
 ...
 </programlisting>
 		</example>