Add back line inadvertantly deleted

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@10822 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

general.ent

@@ -7,6 +7,7 @@
 
 <!ENTITY lfs-root        "http://www.linuxfromscratch.org/">
 <!ENTITY blfs-root       "&lfs-root;blfs/">
+<!ENTITY blfs-book       "&blfs-root;view/&short-version;/"> 
 <!ENTITY faq-root        "&lfs-root;faq/">
 <!ENTITY hints-root      "&lfs-root;hints/downloads/files/">
 <!ENTITY hints-index     "&lfs-root;hints/list.html">