cpumask: IA64: Introduce cpumask_of_{node,pcibus} to replace {node,pcibus}_to_cpumask

Impact: New APIs

The old node_to_cpumask/node_to_pcibus returned a cpumask_t: these
return a pointer to a struct cpumask.  Part of removing cpumasks from
the stack.

We can also use the new for_each_cpu_and() to avoid a temporary cpumask,
and a gratuitous test in sn_topology_show.

(Includes fix from KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tony Luck <tony.luck@intel.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index bd7acc7..54ae373 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -1001,7 +1001,7 @@
 	node = pxm_to_node(pxm);
 
 	if (node >= MAX_NUMNODES || !node_online(node) ||
-	    cpus_empty(node_to_cpumask(node)))
+	    cpumask_empty(cpumask_of_node(node)))
 		return AE_OK;
 
 	/* We know a gsi to node mapping! */