Change in coreboot[master]: cpu/amd/mtrr: Add uma resource based on cbmem_top

[Nico Huber (Code Review)]

Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/36288 )

Change subject: cpu/amd/mtrr: Add uma resource based on cbmem_top
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Patch Set 31:

(1 comment)

https://review.coreboot.org/c/coreboot/+/36288/31/src/cpu/amd/mtrr/amd_mtrr.... 
File src/cpu/amd/mtrr/amd_mtrr.c:

https://review.coreboot.org/c/coreboot/+/36288/31/src/cpu/amd/mtrr/amd_mtrr.... 
PS31, Line 83: 	uint32_t top_of_cacheable = (uint32_t)cbmem_top();
The assumption doesn't hold for soc/amd/, AFAICS. Not sure what to do
about it. Maybe add a

if (!CONFIG(CBMEM_TOP_BACKUP))
            dead_code();

?