[XS] Change in coreboot[main]: drivers/intel/fsp2_0: Use DECLARE_REGION for FSP-M heap

[Shuo Liu (Code Review)]

Attention is currently required from: Andrey Petrov, Arthur Heymans, Chen, Gang C, Felix Held, Julius Werner, Jérémy Compostella, Patrick Rudolph, Ronak Kanabar, Subrata Banik, Werner Zeh.

Shuo Liu has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81097?usp=email )

Change subject: drivers/intel/fsp2_0: Use DECLARE_REGION for FSP-M heap
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Patch Set 4:

(2 comments)

Patchset:

PS3: 
Hi Julius, about the usage of DECLARE_REGION, as of now I'm inclined to still keep it inside if (CONFIG(FSP_SPEC_VIOLATION_XEON_SP_HEAP_WORKAROUND)) otherwise we need to write another #if (CONFIG(FSP_SPEC_VIOLATION_XEON_SP_HEAP_WORKAROUND)) block to include the definition.

PS3:
> Actually, I like that you reference the original patch but I don't think that "fixes" is appropriate […]

Sure, updated.