Added BLFS link and tweaked text on GCC page

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@10670 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

chapter06/gcc.xml

@@ -77,8 +77,9 @@ cd ../gcc-build</userinput></screen>
      --with-system-zlib</userinput></screen>
 
     <para>Note that for other languages, there are some prerequisites that
-    are not available. See the BLFS Book for instructions on how to
-    build all the GCC supported languages.</para>
+    are not yet available. See the
+    <ulink url="&blfs-root;view/svn/general/gcc.html">BLFS Book</ulink>
+    for instructions on how to build all of GCC's supported languages.</para>
 
     <variablelist>
       <title>The meaning of the new configure option:</title>