fix communicator double-free from pt2pt component, caused by r29938.

cmr=v1.7.5:reviewer=brbarret

This commit was SVN r30264.

The following SVN revision numbers were found above:
  r29938 --> open-mpi/ompi@ecfb122c97

ompi/mca/osc/pt2pt/osc_pt2pt_component.c

@@ -339,7 +339,6 @@ component_fragment_cb(ompi_request_t *request)
     if (request->req_status._cancelled) {
         opal_output_verbose(5, ompi_osc_base_framework.framework_output,
                             "pt2pt request was canceled");
-        ompi_request_free(&request);
         return OMPI_ERR_NOT_AVAILABLE;
     }