Show the unreacheable message for the first unreacheable proc
and then stop.
Handle the del_procs correctly. The btl_send is the complete list
of existing BTL fo an endpoint, all the others are just partial list.
Thus, all the cleaning should first be done in the btl_send array,
and them in the other arrays (btl_eager and btl_rdma).
In fact btl_eager and btl_dma will just vanish upon destruction of the
bml_endpoint. No need to clean them bfore.