cpumask: replace node_to_cpumask with cpumask_of_node.

Impact: cleanup

node_to_cpumask (and the blecherous node_to_cpumask_ptr which
contained a declaration) are replaced now everyone implements
cpumask_of_node.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

net/sunrpc/svc.c

@@ -317,8 +317,7 @@ svc_pool_map_set_cpumask(struct task_struct *task, unsigned int pidx)
 	}
 	case SVC_POOL_PERNODE:
 	{
-		node_to_cpumask_ptr(nodecpumask, node);
-		set_cpus_allowed_ptr(task, nodecpumask);
+		set_cpus_allowed_ptr(task, cpumask_of_node(node));
 		break;
 	}
 	}