libpayload: Add access to CMOS images in memory space

libpayload: Add access to CMOS images in memory space

Provide access to CMOS images in RAM or CBFS, such as cmos.defaults

Change-Id: Ifa70dea6206d94c0c271caf9ae1152fc76b5d51a
Signed-off-by: Patrick Georgi <patrick.georgi@secunet.com>
Reviewed-on: http://review.coreboot.org/584
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>