Documentation: remove anticipatory scheduler info

Remove anticipatory block I/O scheduler info from Documentation/
since the code has been deleted.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Reported-by: "Robert P. J. Day" <rpjday@crashcourse.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/Documentation/rbtree.txt b/Documentation/rbtree.txt
index 221f38b..19f8278 100644
--- a/Documentation/rbtree.txt
+++ b/Documentation/rbtree.txt
@@ -21,8 +21,8 @@
 To quote Linux Weekly News:
 
     There are a number of red-black trees in use in the kernel.
-    The anticipatory, deadline, and CFQ I/O schedulers all employ
-    rbtrees to track requests; the packet CD/DVD driver does the same.
+    The deadline and CFQ I/O schedulers employ rbtrees to
+    track requests; the packet CD/DVD driver does the same.
     The high-resolution timer code uses an rbtree to organize outstanding
     timer requests.  The ext3 filesystem tracks directory entries in a
     red-black tree.  Virtual memory areas (VMAs) are tracked with red-black