Add board enable for Bcom WinNET P680.

This patch replaces Alex Mauer's previous patch for this board (from 2008).
Tested to read, erase, and write on 2 different boards, both with AMIC
A29040BL flash chips, using both stock BIOS and coreboot images.

This patch marks the AMIC chip as tested at the same time.

Signed-off-by: Corey Osgood <corey.osgood@gmail.com>
Acked-by: Stefan Tauner <stefan.tauner@student.tuwien.ac.at>

git-svn-id: svn://flashrom.org/flashrom/trunk@1733 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1