Change in coreboot[master]: cpu/amd/agesa/family15tn/model_15_init.c: create correct MTRR solution

[Angel Pons (Code Review)]

Attention is currently required from: Michał Żygowski, Felix Held.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/53991 )

Change subject: cpu/amd/agesa/family15tn/model_15_init.c: create correct MTRR solution
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Patch Set 3: Code-Review+1

(2 comments)

Patchset:

PS3: 
Dooesn't AGESA also do some MTRR programming? Is it still needed?

File src/cpu/amd/agesa/family15tn/model_15_init.c:

https://review.coreboot.org/c/coreboot/+/53991/comment/856daed8_6126e55c 
PS3, Line 39: execution
`AGESA execution`?

I was wondering why Intel platforms don't need this. I suppose it's because AGESA is executed in-place, as opposed to post-RAM coreboot stages and blobs (refcode, FSP-S).