[M] Change in coreboot[main]: drivers/option: Add CBFS file based option backend

[Jérémy Compostella (Code Review)]

Attention is currently required from: Julius Werner, Nicholas Chin, Subrata Banik.

Jérémy Compostella has posted comments on this change by Nicholas Chin. ( https://review.coreboot.org/c/coreboot/+/85905?usp=email )

Change subject: drivers/option: Add CBFS file based option backend
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Patch Set 9:

(3 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/85905/comment/05a46333_139c3189?usp... :
PS9, Line 11: prefix. Options should be stored in cbfs with the option/ prefix. Values
As to my knowledge CBFS is acronym standing for CoreBoot File System CBFS, I would suggest to spell it uppercase.

File src/drivers/option/cbfs_file_option.c:

https://review.coreboot.org/c/coreboot/+/85905/comment/d991c1bb_e13b8ed0?usp... :
PS9, Line 7: unsigned int do_get_uint_option(const char *name, const unsigned int fallback)
Why do we store a uint64_t to retrieve to get an unsigned int (uint32_t)?

File src/include/option.h:

https://review.coreboot.org/c/coreboot/+/85905/comment/34836d2e_f1bb9545?usp... :
PS9, Line 16: 	return fallback;
Shouldn't an error be printed ? A call to get_uint_option() in SMM should be considered an issue as this is not supported.