[PATCH] x86_64: sparsemem does not need node_mem_map

Seems we are trying to init the node_mem_map when we don't need to, for
example when SPARSEMEM is enabled.  This causes the error below during
compilation.  Use CONFIG_FLAT_NODE_MEM_MAP to gate allocation and init.

  arch/x86_64/mm/numa.c: In function `setup_node_zones':
  arch/x86_64/mm/numa.c:191: error: structure has no member
                                                  named `node_mem_map'
Signed-off-by: NAndy Whitcroft <apw@shadowen.org>
Acked-by: NAndi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

arch/x86_64/mm/numa.c

@@ -188,11 +188,13 @@ void __init setup_node_zones(int nodeid)
 	   memory. */
 	memmapsize = sizeof(struct page) * (end_pfn-start_pfn);
 	limit = end_pfn << PAGE_SHIFT;
+#ifdef CONFIG_FLAT_NODE_MEM_MAP
 	NODE_DATA(nodeid)->node_mem_map = 
 		__alloc_bootmem_core(NODE_DATA(nodeid)->bdata, 
 				memmapsize, SMP_CACHE_BYTES, 
 				round_down(limit - memmapsize, PAGE_SIZE), 
 				limit);
+#endif
 
 	size_zones(zones, holes, start_pfn, end_pfn);
 	free_area_init_node(nodeid, NODE_DATA(nodeid), zones,