This commit fixes a long standing bug in rdmacm. It is required that
the thread that calls mca_btl_openib_endpoint_cpc_complete holds the
endpoint lock. This was not the case for rdmacm. This causes debug
builds to abort. This change also required changing
mca_btl_openib_endpoint_send_cts to require the endpoint lock to be
held when calling.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>