fix typo. (role_columns_grants -> role_column_grants)

doc/src/sgml/information_schema.sgml

-<!-- $Header: /cvsroot/pgsql/doc/src/sgml/information_schema.sgml,v 1.10 2003/10/16 23:46:17 petere Exp $ -->
+<!-- $Header: /cvsroot/pgsql/doc/src/sgml/information_schema.sgml,v 1.11 2003/11/03 12:31:52 ishii Exp $ -->
 
 <chapter id="information-schema">
  <title>The Information Schema</title>
@@ -2167,7 +2167,7 @@ ORDER BY c.ordinal_position;
  </sect1>
 
  <sect1 id="infoschema-role-column-grants">
-  <title><literal>role_columns_grants</literal></title>
+  <title><literal>role_column_grants</literal></title>
 
   <para>
    The view <literal>role_column_grants</literal> identifies all