arm: kirkwood: enable DM_ETH for LaCie board

This patch enables DM_ETH for the following Kirkwood-based LaCie boards:

- d2 Network v2
- Internet Space v2
- 2Big Network v2
- Network Space v2
- Network Space Lite v2
- Network Space Max v2
- Network Space Mini v2

Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Reviewed-by: Stefan Roese <sr@denx.de>