Remove now redundant cases in serialize_param and deserialize_param.

This is needed to allow for NDR marshalling rules in reusing memory on
the client side.

Upon failure to allocate results in process_bind_packet, build nack
packet and send right away, instead of falling into the normal path
and potentially dereferencing the NULL pointer.

We now only delete the node contents in these functions.

Not only is it not related to property set storages, it's also not the root
of the tree that's used to search for elements.