Change in coreboot[master]: option: Add API for mainboard provided options

[Patrick Rudolph (Code Review)]

Attention is currently required from: Bill XIE, Nico Huber, Patrick Rudolph, Christian Walter, Julius Werner, Kyösti Mälkki.
Hello build bot (Jenkins), Bill XIE, Nico Huber, Christian Walter, Julius Werner, Kyösti Mälkki,

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

https://review.coreboot.org/c/coreboot/+/52601

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

Change subject: option: Add API for mainboard provided options
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option: Add API for mainboard provided options

This API can be implemented by mainboards providing a custom option storage.
For example an external I2C EEPROM, IPMI on BMC, ...

Update documentation accordingly.

Change-Id: Ic5bbb5b3353d862c5533f90ced4824eec27ca3b9
Signed-off-by: Patrick Rudolph 
---
M Documentation/index.md
A Documentation/lib/option.md
M src/Kconfig
3 files changed, 41 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/01/52601/2