fix is_headless_node() for systems w/<64p

I didn't realize that any_online_cpu() wouldn't work for is_headless_node(), so this patch reverts the function back to using the node_to_cpu_mask[] array, fixing sn2 for systems with less than 64p.

Thanks,
Jesse

=== include/asm-ia64/sn/nodepda.h 1.9 vs edited ==--- 1.9/include/asm-ia64/sn/nodepda.h Tue Sep 9 04:19:45 2003
+++ edited/include/asm-ia64/sn/nodepda.h Wed Oct 1 10:28:12 2003
@@ -128,7 +128,7 @@
* Check if given a compact node id the corresponding node has all the
* cpus disabled.
*/
-#define is_headless_node(cnode) (!any_online_cpu(node_to_cpumask(cnode)))
+#define is_headless_node(cnode) (!node_to_cpu_mask[cnode])

/*
* Check if given a node vertex handle the corresponding node has all the