re-added ld.so.conf touching explanation

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@1915 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

chapter06/glibc-exp.xml

@@ -1,6 +1,12 @@
 <sect2>
 <title>Command explanations</title>
 
+<para><userinput>touch /etc/ld.so.conf:</userinput> One of the final steps
+of the Glibc installation is running ldconfig to update the dynamic loader
+cache. If this file doesn't exist, the installation will abort with an error
+that it can't read the file, so we simply create an empty file (the empty
+file will have Glibc default to using /lib and /usr/lib which is fine).</para>
+
 <para><userinput>sed 's%\$(PERL)%/usr/bin/perl%' 
 malloc/Makefile.backup &gt; malloc/Makefile:</userinput> This sed command
 searches through <filename>malloc/Makefile.backup</filename> and