Rename eth_stream into eth_stream_udp. Create new eth_stream.vhd that contains...

Closes L2SDP-864

See merge request desp/hdl!293

Correct wr_fifo_usedw, it gets already assigned in dp_fifo_core. To avoid tristate insertion in synthesis due to double driver.

Rename eth_stream into eth_stream_udp. Create new eth_stream.vhd that contains complete ETH interface component with eth_stream_udp and tech_tse_with_setup.

Use default 0 for nxt_info to avoid X to decimal conversion error in sim_io.py...

Closes L2SDP-864

See merge request desp/hdl!292