[PATCH] cpu_exclusive sched domains build fix

As reported by Paul Mackerras <paulus@samba.org>, the previous patch
"cpu_exclusive sched domains fix" broke the ppc64 build with
CONFIC_CPUSET, yielding error messages:

kernel/cpuset.c: In function 'update_cpu_domains':
kernel/cpuset.c:648: error: invalid lvalue in unary '&'
kernel/cpuset.c:648: error: invalid lvalue in unary '&'

On some arch's, the node_to_cpumask() is a function, returning
a cpumask_t.  But the for_each_cpu_mask() requires an lvalue mask.

The following patch fixes this build failure by making a copy
of the cpumask_t on the stack.
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

kernel/cpuset.c

@@ -645,7 +645,9 @@ static void update_cpu_domains(struct cpuset *cur)
 		int i, j;
 
 		for_each_cpu_mask(i, cur->cpus_allowed) {
-			for_each_cpu_mask(j, node_to_cpumask(cpu_to_node(i))) {
+			cpumask_t mask = node_to_cpumask(cpu_to_node(i));
+
+			for_each_cpu_mask(j, mask) {
 				if (!cpu_isset(j, cur->cpus_allowed))
 					return;
 			}