Custom patch from Brice for the hwloc-1.2.2ompi distro, per an issue

that Chris Yeoh/IBM found.  See the thread below for more info:

  http://www.open-mpi.org/community/lists/hwloc-devel/2011/11/2521.php

This commit was SVN r25429.

opal/mca/hwloc/hwloc122ompi/hwloc/src/distances.c

@@ -342,6 +342,10 @@ hwloc_setup_distances_from_os_matrix(struct hwloc_topology *topology,
     return;
   }
   hwloc_bitmap_free(set);
+  if (root->depth >= objs[0]->depth) {
+    /* strange topology led us to find invalid relative depth, ignore */
+    return;
+  }
   relative_depth = objs[0]->depth - root->depth; /* this assume that we have distances between objects of the same level */
 
   /* get the logical index offset, it's the min of all logical indexes */