Change in coreboot[master]: mb/google/brya/var/baseboard/brask: Add power limits functions

[Alan Huang (Code Review)]

Attention is currently required from: Hou-hsun Lee, Paul Menzel, Nick Vaccaro, Zhuohao Lee.
Alan Huang has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/58241 )

Change subject: mb/google/brya/var/baseboard/brask: Add power limits functions
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Patch Set 15:

(2 comments)

Patchset:

PS15: 
Removed psys_pmax_power from struct system_power_limits as the field is actually not used.
Added more comments in variants.h for function variants_update_psys_power_limits

File src/mainboard/google/brya/variants/baseboard/brask/ramstage.c:

https://review.coreboot.org/c/coreboot/+/58241/comment/683f729b_b0056f7d 
PS14, Line 108: 	soc_config->tdp_pl4 = 0;
> You set tdp_pl4 to 0 here, which means you must call variant_update_psys_power_limits() first, then  […]

Yes, it's correct. Added comments in variants.h.