Remove a hard coded version number

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@11544 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

chapter06/libffi.xml

@@ -52,7 +52,7 @@
 
     <para>Modify the Makefile to install headers into the standard
     <filename class="directory">/usr/include</filename> directory instead of
-    <filename class="directory">/usr/lib/libffi-3.2.1/include</filename>.</para>
+    <filename class="directory">/usr/lib/libffi-&libffi-version;/include</filename>.</para>
 
 <screen><userinput remap="pre">sed -e '/^includesdir/ s/$(libdir).*$/$(includedir)/' \
     -i include/Makefile.in