cores: add mt46v16m16p DDR2 memory model

Signed-off-by: Franck Jullien <franck.jullien@gmail.com>
cores: add wb_altera_ddr_wrapper

Signed-off-by: Franck Jullien <franck.jullien@gmail.com>
systems: add Altera NEEK board

This patch adds supports for the Altera NEEK board.
For now, the systems contains a gpio, uart and a VGA/LCD controller.

Signed-off-by: Franck Jullien <franck.jullien@gmail.com>