Change in coreboot[master]: src/acpi: Add initial support for HMAT

[Jonathan Zhang (Code Review)]

Attention is currently required from: Anjaneya "Reddy" Chagam, Tim Wawrzynczak, David Hendricks, Stefan Reinauer, Angel Pons, Subrata Banik.
Jonathan Zhang has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/52047 )

Change subject: src/acpi: Add initial support for HMAT
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Patch Set 5:

(2 comments)

File src/include/acpi/acpi.h:

https://review.coreboot.org/c/coreboot/+/52047/comment/2fe9c88f_2f2e36ab 
PS5, Line 242: u8 min_transfer_size;
> this has a slightly odd definition, a comment may be helpful

Ack

https://review.coreboot.org/c/coreboot/+/52047/comment/f2a62eb8_1656edc9 
PS5, Line 261: 	u32 cache_attributes
> Some `enum`s or `#define` values could be useful to describe this bitfield

Makes sense, this will be done in a follow-up patch. For now, I will add a comment to describe the field.