Change in coreboot[master]: src/lib: Add FW_CONIFG_SOURCE_VPD

[Tim Wawrzynczak (Code Review)]

Attention is currently required from: Jamie Ryu, Wonkyu Kim, Ravishankar Sarawadi, Julius Werner, Subrata Banik, Nick Vaccaro, Srinidhi N Kaushik, Raj Astekar.
Tim Wawrzynczak has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/58839 )

Change subject: src/lib: Add FW_CONIFG_SOURCE_VPD
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Patch Set 4:

(3 comments)

File src/Kconfig:

https://review.coreboot.org/c/coreboot/+/58839/comment/0268b3d6_ed313eb3 
PS4, Line 421: depends on FW_CONFIG
`depends on FW_CONFIG && VPD`

File src/lib/fw_config.c:

https://review.coreboot.org/c/coreboot/+/58839/comment/d1a7df99_d456ebbc 
PS4, Line 51: int32_t
nit: `int`, then no casting is needed below?

https://review.coreboot.org/c/coreboot/+/58839/comment/97aafee9_f5c5047c 
PS4, Line 59: fw_config_value = UNDEFINED_FW_CONFIG;
this line is redundant