arm: orion5x: convert 'LaCie Ethernet Disk mini v2' to Device Tree

This commit converts the 'LaCie Ethernet Disk mini v2' board to the
Device Tree. All devices that have existing Device Tree bindings are
converted over to the Device Tree, the other devices remain
instantiated in the old way, until the respective drivers get the
needed Device Tree bindings.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested by: Maxime Hadjinlian <mhadjinlian@lacie.com>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>