Rendezvous does not work with TCP stack

[Christian Tinnefeld]

The invocation of the callback assign_data_in_buf (aka Rendezvous) implies calling the the xio memory allocator (xio_mem_alloc). However, calling xio_mem_alloc only works when IB hardware is present, otherwise the invocation of the allocator fails since there are no Infiniband devices present.

As a workaround I tried to allocate memory just with malloc and I even tried to mimic the creation of the xio stack internal memorr region object, but my attempt failed.

Please advice how to procees here as imho it is not possible right now to send larger data items over TCP.