Fix segmentation fault when osc_rdma is used with pml_cm: osc_rdma 
assumes the send request is derived from mca_pml_base_send_request_t,
but this is not true for pml cm, so we end up freeing invalid pointer.
 We cannot take the data pointer from the pml send request, so we pass 
the allocated buffer pointer in req_complete_cb_data, and put the 
osc_rdma_module pointer in that buffer as well.
 Previously, osc_pt2pt was used with pml_cm which didn't have this 
problem.

cmr=v1.7.5:reviewer=ompi-rm1.7
When pretty-printing binding info, we need to pass the topology down to the routine as the mapper isn't always working with the local topology - otherwise, we get an erroneous help message. Thanks to Tetsuya Mishima for reporting it

cmr=v1.7.5:reviewer=rhc:subject=fix pretty-print of bindings