This implements support for devices using AMD Geode companion chip

This implements support for devices using AMD Geode companion chip
CS5536 that have the Boot ROM on NOR flash that is directly connected to
FLASH_CS3 (Boot Flash Chip Select).
We need to write enable it in the NORF_CTL MSR register for flashrom to
be able to write to it, including JEDEC probe commands.

This patch allows us to stop using AMD gx_utils.ko for BIOS flashing on
the DBE61.

Signed-off-by: Mart Raudsepp <mart.raudsepp@artecdesign.ee>
Acked-by: Uwe Hermann <uwe@hermann-uwe.de>
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@3097 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1