Change in coreboot[master]: drivers/efi: Add EFI variable store option support

[Patrick Rudolph (Code Review)]

Attention is currently required from: Sean Rhodes, Michał Żygowski, Martin Roth, Jakub Czapiga, Matt DeVillier, Patrick Rudolph.
Patrick Rudolph has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/52564 )

Change subject: drivers/efi: Add EFI variable store option support
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Patch Set 10:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/52564/comment/e9ce9b2e_581ab0e3 
PS5, Line 18: - Init store with FVH when blank
> Yes, I think coreboot should initialize it. […]

Updated the commit message with more information. Is that fine for you?

https://review.coreboot.org/c/coreboot/+/52564/comment/bb8af68a_72fc61a1 
PS5, Line 20: - Reclaim memory when store is full
> The store is write-append. You write a new variable at the end and mark the old as "deleted". […]

Updated the commit message with more information. Is that fine for you?