This patch adds the get_spd_sn function. It's for reading SODIMM serial
number. In spd_cache implementation it can use to get serial number
before reading whole SPD by smbus.
BUG=b:146457985
BRANCH=None
TEST=Wrote sample code to get the serial number and ran on puff.
It can get the serial number correctly.
Change-Id: I406bba7cc56debbd9851d430f069e4fb96ec937c
Signed-off-by: Jamie Chen <jamie.chen@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40414
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
7adcfde079