Remove unused MAX_NODES_SHIFT

MAX_NODES_SHIFT is not referenced anywhere in the tree, so dump it.
Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>

include/linux/mmzone.h

@@ -699,7 +699,6 @@ extern char numa_zonelist_order[];
 extern struct pglist_data contig_page_data;
 #define NODE_DATA(nid)		(&contig_page_data)
 #define NODE_MEM_MAP(nid)	mem_map
-#define MAX_NODES_SHIFT		1
 
 #else /* CONFIG_NEED_MULTIPLE_NODES */