Fix GH-1398: PDO::pgsqlGetNotify inconsistent return type

Author: cmb69

reference/pdo_pgsql/PDO/pgsqlGetNotify.xml

@@ -8,7 +8,7 @@
  <refsect1 role="description">
   &reftitle.description;
   <methodsynopsis>
-   <modifier>public</modifier> <type>array</type><methodname>PDO::pgsqlGetNotify</methodname>
+   <modifier>public</modifier> <type class="union"><type>array</type><type>false</type></type><methodname>PDO::pgsqlGetNotify</methodname>
    <methodparam choice="opt"><type>int</type><parameter>result_type</parameter><initializer><constant>PDO::FETCH_USE_DEFAULT</constant></initializer></methodparam>
    <methodparam choice="opt"><type>int</type><parameter>ms_timeout</parameter><initializer>0</initializer></methodparam>
   </methodsynopsis>