[S] Change in coreboot[main]: payloads/depthcharge: Add default 64-bit libpayload config

[Cliff Huang (Code Review)]

Attention is currently required from: Anil Kumar K, Bora Guvendik, Jérémy Compostella, Martin L Roth, Paul Menzel, Subrata Banik, Wonkyu Kim.

Cliff Huang has posted comments on this change by Cliff Huang. ( https://review.coreboot.org/c/coreboot/+/84107?usp=email )

Change subject: payloads/depthcharge: Add default 64-bit libpayload config
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Patch Set 9:

(1 comment)

File payloads/libpayload/configs/defconfig_64:

https://review.coreboot.org/c/coreboot/+/84107/comment/07c5c9ac_4ae93af3?usp... :
PS8, Line 1: # NOTE: remove to test _LP64 issue: CONFIG_LP_ARCH_X86_64=y
> If this is commented out it's same as defconfig. […]

Yes. I think it is related, but not sure how to build 3rdparty/cmocka/ which will build libpayload/tests/mock. In our build, we don't build tests directory under libpayload.