[M] Change in coreboot[master]: mb/google/rex: Implement S0ix hooks aka `MS0X` method

[Utkarsh H Patel (Code Review)]

Attention is currently required from: Subrata Banik, Kapil Porwal, Ivy Jian, Sridhar Siricilla, Eric Lai, Utkarsh H Patel.

Utkarsh H Patel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/70196 )

Change subject: mb/google/rex: Implement S0ix hooks aka `MS0X` method
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Patch Set 5:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/70196/comment/ee0f3b5e_466b9c8f 
PS5, Line 10: on the state of the system while `SKL_S0_L` signal is `low` (while
SLP_S0_L