usnic: avoid a possible race condition

Per #4874, code review revealed a possible race condition in the
module struct and the connectivity agent.  Move the setup of the
connectivity agent listener until the module struct has been fully
setup.

This commit was SVN r32573.

opal/mca/btl/usnic/btl_usnic_module.c

@@ -2086,19 +2086,6 @@ int opal_btl_usnic_module_init(opal_btl_usnic_module_t *module)
                         "btl:usnic: not sorting devices by NUMA distance (topology support not included)");
 #endif
 
-    /* Setup a connectivity listener */
-    if (mca_btl_usnic_component.connectivity_enabled) {
-        rc = opal_btl_usnic_connectivity_listen(module);
-        if (OPAL_SUCCESS != rc) {
-            OPAL_ERROR_LOG(rc);
-            ABORT("Failed to notify connectivity agent to listen");
-        }
-    } else {
-        /* If we're not doing a connectivity check, just set the port
-           to 0 */
-        module->local_addr.connectivity_udp_port = 0;
-    }
-
     /* Setup the pointer array for the procs that will be used by this
        module */
     OBJ_CONSTRUCT(&module->all_procs, opal_pointer_array_t);
@@ -2288,6 +2275,19 @@ int opal_btl_usnic_module_init(opal_btl_usnic_module_t *module)
     /* Initialize stats on this module */
     opal_btl_usnic_stats_init(module);
 
+    /* Setup a connectivity listener */
+    if (mca_btl_usnic_component.connectivity_enabled) {
+        rc = opal_btl_usnic_connectivity_listen(module);
+        if (OPAL_SUCCESS != rc) {
+            OPAL_ERROR_LOG(rc);
+            ABORT("Failed to notify connectivity agent to listen");
+        }
+    } else {
+        /* If we're not doing a connectivity check, just set the port
+           to 0 */
+        module->local_addr.connectivity_udp_port = 0;
+    }
+
     return OPAL_SUCCESS;
 
 chan_destroy: