x86: fix memoryless node oops during boot

fix oops during boot reported in this thread:

  http://lkml.org/lkml/2008/2/6/65

enable booting on memoryless nodes.
Reported-by: NKamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

arch/x86/kernel/setup_64.c

@@ -801,7 +801,7 @@ static void __cpuinit srat_detect_node(void)
 	/* Don't do the funky fallback heuristics the AMD version employs
 	   for now. */
 	node = apicid_to_node[apicid];
-	if (node == NUMA_NO_NODE)
+	if (node == NUMA_NO_NODE || !node_online(node))
 		node = first_node(node_online_map);
 	numa_set_node(cpu, node);