[S] Change in coreboot[main]: symbols: Add __maybe_unused flag to region variable symbols

[Martin L Roth (Code Review)]

Attention is currently required from: Arthur Heymans, Julius Werner, Jérémy Compostella, Lean Sheng Tan, Patrick Rudolph, Shuo Liu.

Martin L Roth has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81209?usp=email )

The change is no longer submittable: All-Comments-Resolved is unsatisfied now.

Change subject: symbols: Add __maybe_unused flag to region variable symbols
......................................................................

Patch Set 4: Code-Review+2

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/81209/comment/43dd3a87_86dd8657 :
PS4, Line 12: comipler
compiler

Patchset:

PS4: 
Good after fixing a typo in the commit message.  Thanks.