Fix issue with the error reporting as suggested by Gilles.

ompi/mca/coll/tuned/coll_tuned_barrier.c

@@ -82,9 +82,9 @@ ompi_coll_tuned_sendrecv_zero(int dest, int stag,
          * code that we can propagate up the stack. Instead, look for the real
          * error code from the MPI_ERROR in the status.
          */
-        int err_index = 1;
+        int err_index = 0;
         if( MPI_SUCCESS == statuses[0].MPI_ERROR ) {
-            err_index = 0;
+            err_index = 1;
         }
         err = statuses[err_index].MPI_ERROR;
         OPAL_OUTPUT ((ompi_coll_tuned_stream, "%s:%d: Error %d occurred in the %s"