[S] Change in coreboot[main]: src/lib: Add Kconfig variable for fw_config default value

[Cliff Huang (Code Review)]

Attention is currently required from: Bora Guvendik, Subrata Banik, Wonkyu Kim.

Cliff Huang has posted comments on this change by Cliff Huang. ( https://review.coreboot.org/c/coreboot/+/83153?usp=email )

Change subject: src/lib: Add Kconfig variable for fw_config default value
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Patch Set 1:

(1 comment)

File src/Kconfig:

https://review.coreboot.org/c/coreboot/+/83153/comment/b81afae3_6f398b6f?usp... :
PS1, Line 548: 0x01000
> Is there any reason why this value is no-zero value?

okay. undefined value is non-zero, I will change default value to '0'

./src/include/fw_config.h:
#define UNDEFINED_FW_CONFIG	~((uint64_t)0)