Change in coreboot[master]: chromeos: Add an elog for Chrome OS diagnostic boot

[Hsuan-ting Chen (Code Review)]

Attention is currently required from: Hsuan Ting Chen, Paul Menzel, Julius Werner, Yu-Ping Wu, Aaron Durbin.
Hsuan-ting Chen has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/54948 )

Change subject: chromeos: Add an elog for Chrome OS diagnostic boot
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Patch Set 7:

(5 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/54948/comment/6e4e2aa9_d43cb3b6 
PS6, Line 7: diagnostics
> diagnostic

Done

https://review.coreboot.org/c/coreboot/+/54948/comment/2f3dd683_2cf368f2 
PS6, Line 10: logging
> log

Done

https://review.coreboot.org/c/coreboot/+/54948/comment/74970ba3_676ade58 
PS6, Line 15: request request
> request

Done

https://review.coreboot.org/c/coreboot/+/54948/comment/01e33ba0_89545769 
PS6, Line 15: diagnostics
> diagnostic

Done

Patchset:

PS7: 
This can still not merge until vboot boot_mode landed and uprev maded