Add missing fullstop

Author: vrana

reference/session/ini.xml

@@ -230,7 +230,7 @@
      <entry><link linkend="ini.session.entropy-length">session.entropy_length</link></entry>
      <entry>"0"</entry>
      <entry><constant>INI_ALL</constant></entry>
-     <entry>Removed as of PHP 7.1.0</entry>
+     <entry>Removed as of PHP 7.1.0.</entry>
     </row>
    </tbody>
   </tgroup>