Remove pg_pageprep from RN 9.6.9.1

Author: dmpgpro

doc/src/sgml/release-pro-9.6.sgml

@@ -15,14 +15,6 @@
     <para>Major enhancements over <productname>Postgres Pro Standard</productname>
       9.6.8.2 include:</para>
     <itemizedlist>
-      <listitem>
-        <para>Added <filename>pg_pageprep</filename> module to facilitate
-          migration from <productname>PostgreSQL</productname>-based
-          products that use 32-bit transaction IDs to
-          <productname>Postgres Pro Enterprise</productname> 10 that uses 64-bit
-          transaction IDs. (See <xref linkend="pg-pageprep">.)</para>
-        <!-- 2bf163ae1814b03dc23d76999f6938d965d2671f -->
-      </listitem>
       <listitem>
         <para>Updated the <xref linkend="mchar"> to fix the sorting order for
           Cyrillic letters Yo and short I.