Change in coreboot[master]: intelblocks/pep: Add display on/off notifications

[Felix Held (Code Review)]

Attention is currently required from: Michał Żygowski, Michał Kopeć, Tim Wawrzynczak, Angel Pons, Patrick Rudolph.
Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62494 )

Change subject: intelblocks/pep: Add display on/off notifications
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Patch Set 5:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/62494/comment/c30211ab_359499a3 
PS3, Line 8: 
           : Add display on and off notifications which call mainboard hooks if
           : present. This allows to handle some board specific functions in user
           : absence or presence (whe ndisplay goes off from inactivity or on from
           : activity).
           : 
           : Additionally notify IOM to enable or disable TBT displays on S0ix
           : exit and entry respectively.
> Moved TBT related changes to CB:63980

Done