mb/intel/dg41wv: Add mainboard

This board was used a test target for the x4x DDR3 raminit patches and
has an easy to access DIP8 socket.

What is tested and works:
* S3 resume
* PEG, PCI, USB, SATA
* Sound
* Ethernet
* Native graphic init (textmode and linear fb) on the VGA output
* Passing memtest86+ with 2 2Rx8 4G dimms
* PS2 Keyboard
* Flashing coreboot internally from vendor BIOS.

What does not work:
* Running dram at 533 MHz (limited at 400MHz currently)

Tested with two 4G dual rank DDR3 dimm, booted SeaBIOS and Linux
4.10.

Change-Id: If01bf658e52d273c3c203d362f21c3cb9c623f40
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/20003
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
18 files changed