[coreboot-gerrit] Change in coreboot[master]: Documentation: Update index.md and add 4.18 release notes

[Felix Singer (Code Review)]

Attention is currently required from: Martin L Roth, Julius Werner.
Felix Singer has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/64843 )

Change subject: Documentation: Update index.md and add 4.18 release notes
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Patch Set 1:

(1 comment)

File Documentation/releases/coreboot-4.18-relnotes.md:

https://review.coreboot.org/c/coreboot/+/64843/comment/2c6d0dd1_9c033aa9 
PS1, Line 17:
> When you want to deprecate something, this should be announced 6 months before.

Sorry, I meant: If you want to remove something, then it should be announced 6 months before. The announcement itself makes that thing deprecated.