[S] Change in coreboot[main]: drivers/vpd: Add vpd_get_feature_level() API

[Subrata Banik (Code Review)]

Attention is currently required from: Gwendal Grignou, Kapil Porwal, Nick Vaccaro, Shelley Chen.

Hello Gwendal Grignou, Kapil Porwal, Nick Vaccaro, Shelley Chen, build bot (Jenkins),

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/80805?usp=email

to look at the new patch set (#2).

The following approvals got outdated and were removed:
Code-Review+2 by Kapil Porwal, Code-Review-1 by Gwendal Grignou, Verified+1 by build bot (Jenkins)

Change subject: drivers/vpd: Add vpd_get_feature_level() API
......................................................................

drivers/vpd: Add vpd_get_feature_level() API

This patch introduces the vpd_get_feature_level() API to specifically
extract the "feature_level" field from the "feature_device_info" VPD
key.

This is used to distinguish between Chromebook-Plus and regular
Chromebook devices.

The previous vpd_get_feature_device_info() API is removed as
vpd_get_feature_level() is enough to find VPD and extract the data.

Note: The new API decodes the base64-encoded "feature_device_info" VPD
data.

BUG=b:324107408
TEST=Able to build and boot google/rex0.

Change-Id: I76fc220ed792abdfefb0b1a37873b5b828bfdda8
Signed-off-by: Subrata Banik 
---
M src/drivers/vpd/vpd.h
M src/drivers/vpd/vpd_device_feature.c
2 files changed, 33 insertions(+), 9 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/05/80805/2