Fix SGML markup for upgrade doc addition.

doc/src/sgml/runtime.sgml

 <!-- doc/src/sgml/runtime.sgml -->
 
-<chapter Id="runtime">
+<chapter id="runtime">
  <title>Server Setup and Operation</title>
 
  <para>
@@ -1611,9 +1611,9 @@ $ <userinput>kill -INT `head -1 /usr/local/pgsql/data/postmaster.pid`</userinput
 <screen>
 <userinput>/etc/rc.d/init.d/postgresql stop</userinput>
 </screen>
-     </para>
       See <xref linkend="runtime"> for details about starting and
       stoping the server.
+     </para>
     </step>
 
     <step>