ie31200_edac: Introduce the driver

Add a driver for the E3-1200 series of Intel DRAM controllers, based on
the following E3-1200 specs:

http://www.intel.com/content/www/us/en/processors/xeon/xeon-e3-1200-family-vol-2-datasheet.html
http://www.intel.com/content/www/us/en/processors/xeon/xeon-e3-1200v3-vol-2-datasheet.html

I've tested this on bad memory hardware, and observed correlating bad
reads and uncorrected memory errors as reported by the driver.

Tested against:

CPU E3-1270 v3 @ 3.50GHz : 8086:0c08 (haswell)
CPU E3-1270 V2 @ 3.50GHz : 8086:0158 (ivy bridge)
CPU E31270 @ 3.40GHz : 8086:0108 (sandy bridge)

Signed-off-by: Jason Baron <jbaron@akamai.com>
Link: http://lkml.kernel.org/r/95c83e80dd40b5377e8bb206285c5d95ac623872.1403818526.git.jbaron@akamai.com
[ Boris: realign defines ]
Signed-off-by: Borislav Petkov <bp@suse.de>