Small typos in Hot Standby docs

Here's a patch:

diff --git a/doc/src/sgml/backup.sgml b/doc/src/sgml/backup.sgml
index 6750db8..1276c39 100644
*** a/doc/src/sgml/backup.sgml
--- b/doc/src/sgml/backup.sgml
*************** if (!triggered)
*** 2018,2024 ****     <itemizedlist>      <listitem>       <para>
!        Data Definition Language (DML) - INSERT, UPDATE, DELETE, COPY
FROM, TRUNCATE.        Note that there are no allowed actions that result in a trigger        being executed during
recovery.      </para>
 
--- 2018,2024 ----     <itemizedlist>      <listitem>       <para>
!        Data Manipulation Language (DML) - INSERT, UPDATE, DELETE,
COPY FROM, TRUNCATE.        Note that there are no allowed actions that result in a trigger        being executed
duringrecovery.       </para>
 
*************** if (!triggered)
*** 2164,2170 ****        <listitem>         <para>          Dropping tablespaces on the primary while standby queries
areusing
 
!          those tablespace for temporary work files (work_mem overflow)         </para>        </listitem>
<listitem>
--- 2164,2170 ----        <listitem>         <para>          Dropping tablespaces on the primary while standby queries
areusing
 
!          those tablespaces for temporary work files (work_mem overflow)         </para>        </listitem>
<listitem>