This patch adds support for the NAND flash present on Compulab's cm-x255 boards. Since 
Compulab chose to discontinue cm-x255 support, I decided to submit and support this driver 
myself.

Note: This is the driver I wrote as part of my Compulab kernel fork project (see 
http://raph.people.8d.com/armcore_kernel.php). It is not based on the driver Mike posted 
to the list.

Applies to 2.6.18-rc2.

Signed-off-by: Raphael Assenat <raph@8d.com>