OSHMEM: finalization fixes

Fixes mxm endpoint destruction and hung during
SHMEM finalization.

Add a barrier between spml del procs and finalization.
Not having it caused hungs because ikrit spml can not properly
disconnect if its peer already finizalized.

Refs trac:3763

This commit was SVN r30572.

The following Trac tickets were found above:
  Ticket 3763 --> https://svn.open-mpi.org/trac/ompi/ticket/3763

oshmem/mca/spml/ikrit/spml_ikrit.c

@@ -343,16 +343,14 @@ int mca_spml_ikrit_del_procs(oshmem_proc_t** procs, size_t nprocs)
     size_t i;
     opal_list_item_t *item;
 
-    if (mca_spml_ikrit.mxm_ep) {
-        mxm_ep_destroy(mca_spml_ikrit.mxm_ep);
-        mca_spml_ikrit.mxm_ep = 0;
-    }
-
     while (NULL != (item = opal_list_remove_first(&mca_spml_ikrit.active_peers))) {
     };
     OBJ_DESTRUCT(&mca_spml_ikrit.active_peers);
 
     for (i = 0; i < nprocs; i++) {
+        if (mca_spml_ikrit.mxm_peers[i]->mxm_conn) {
+            mxm_ep_disconnect(mca_spml_ikrit.mxm_peers[i]->mxm_conn);
+        }
         destroy_ptl_idx(i);
         if (mca_spml_ikrit.mxm_peers[i]) {
             OBJ_RELEASE(mca_spml_ikrit.mxm_peers[i]);

oshmem/runtime/oshmem_shmem_finalize.c

@@ -130,6 +130,8 @@ static int _shmem_finalize(void)
         return ret;
     }
 
+    oshmem_shmem_barrier();
+
     /* free spml resource */
     if (OSHMEM_SUCCESS != (ret = mca_spml_base_finalize())) {
         return ret;