Change in coreboot[master]: mb/google/brya/var/kano: Update TDP PL1, PL2, and PL4 for U28 SKUs

[Peter Ou (Code Review)]

Attention is currently required from: David Wu, Tim Wawrzynczak, Ren Kuo, Sumeet R Pawnikar, Nick Vaccaro, Alan Huang.
Peter Ou has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62466 )

Change subject: mb/google/brya/var/kano: Update TDP PL1, PL2, and PL4 for U28 SKUs
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Patch Set 3:

(1 comment)

File src/mainboard/google/brya/variants/kano/ramstage.c:

https://review.coreboot.org/c/coreboot/+/62466/comment/3c4dffca_9b71f562 
PS3, Line 10: 20000
> Added you to the bug.

This change base on thermal capacity, our thermal design target is 18~20w for U28 sku.
before change:  PL1 is 28W, PL2 is 40w
1. Octane 2.0 score is 81991
2. speedometer2 score is 257

After change: PL1 to 20W, PL2 change 43w
1. Octane 2.0 score is 85148
2. speedometer2 score is 259
3. look like the performance is better when the PL1/PL2 be change in CB.