MTL/MXM: call for ompi_proc_world instead of ompi_comm_size during del_procs.

This commit was SVN r32504.

ompi/mca/mtl/mxm/mtl_mxm.c

@@ -506,9 +506,12 @@ int ompi_mtl_mxm_del_procs(struct mca_mtl_base_module_t *mtl, size_t nprocs,
     size_t i;
 
 #if MXM_API >= MXM_VERSION(3,1)
-    if (ompi_mtl_mxm.bulk_disconnect &&
-            nprocs == ompi_comm_size(&ompi_mpi_comm_world.comm)) {
-        mxm_ep_powerdown(ompi_mtl_mxm.ep);
+    if (ompi_mtl_mxm.bulk_disconnect) {
+        size_t nprocs_world;
+        ompi_proc_world(&nprocs_world);
+        if (nprocs == nprocs_world) {
+            mxm_ep_powerdown(ompi_mtl_mxm.ep);
+        }
     }
 #endif