patch explanation added

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@830 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

chapter06/shadowpwd-inst.xml

@@ -1,7 +1,10 @@
 <sect2>
 <title>Installation of Shadow Password Suite</title>
 
-<para>Install the Shadow Password Suite by running the following commands:</para>
+<para>Before the shadow Password Suite can be installed, the patch file
+must be unpacked.  This patch fixes a compliation problem due to a
+variable being used but not defined.  Install the Shadow Password 
+Suite by running the following commands:</para>
 
 <para><screen><userinput>patch -Np1 -i ../shadow-20001016.patch &amp;&amp;</userinput>
 <userinput>./configure --prefix=/usr &amp;&amp;</userinput>