Driver for Beckhoff CX5020 EtherCAT master module.

This driver adds support for EtherCAT master module located on CCAT
FPGA found on Beckhoff CX series industrial PCs. The driver exposes
EtherCAT master as an ethernet interface.

EtherCAT is a fieldbus protocol defined on top of ethernet and Beckhoff
CX5020 PCs come with built-in EtherCAT master module located on a FPGA,
which in turn is connected to a PCI bus.

Signed-off-by: Dariusz Marcinkiewicz <reksio@newterm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>