[M] Change in coreboot[main]: mb/google/brox: Remove Platform(PSys) related implementation

[Ashish Kumar Mishra (Code Review)]

Attention is currently required from: Sowmya Aralguppe.

Ashish Kumar Mishra has posted comments on this change by Sowmya Aralguppe. ( https://review.coreboot.org/c/coreboot/+/84397?usp=email )

Change subject: mb/google/brox: Remove Platform(PSys) related implementation
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Patch Set 3:

(3 comments)

Patchset:

PS3: 
This commit will break other brox variant builds.

File src/mainboard/google/brox/variants/baseboard/include/baseboard/variants.h:

https://review.coreboot.org/c/coreboot/+/84397/comment/830a6056_e6d43d93?usp... :
PS3, Line 58: struct psys_config {
Please update this struct reference in other brox variants, as well. Such as variants/jubilant. They are using same header.

https://review.coreboot.org/c/coreboot/+/84397/comment/65f1a1af_5fa72557?usp... :
PS3, Line 82: void variant_update_psys_power_limits(const struct cpu_power_limits *limits,
Please update this function call reference in other brox variants, as well. Such as variants/jubilant. They are using same header from baseboard.