Change in coreboot[master]: mb/google/corsola: Revise power-on sequence of PS8640

[Rex-BC Chen (Code Review)]

Attention is currently required from: Hung-Te Lin, Paul Menzel.
Rex-BC Chen has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62893 )

Change subject: mb/google/corsola: Revise power-on sequence of PS8640
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Patch Set 6:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/62893/comment/b7dd3184_c30d3613 
PS5, Line 9: The power-on sequence of PS8640 needs to be modified because the
           : waveform of power-on sequence do not meet the spec of PS8640.
> no, just not meet power-on spec measured by oscilloscope.

Done

https://review.coreboot.org/c/coreboot/+/62893/comment/1913dc56_daae2cf9 
PS5, Line 17: result of waveform meets the spec.
> I add power-on sequence in commit message: […]

Done