[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, Martin L Roth, 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 1:

(1 comment)

Patchset:

PS1:
> I assume this is for standalone build of coreboot? you don't need anything specifically to build 64- […]

Correct. This is used in standalone environment. The existing paylloads/libpayload/configs/deconfig is for older boards with 32-bit and we need another one for 64-bit, but we want to avoid using specific paylloads/libpayload/configs/board.[board name] file such as board.ptlrvp64 in the environment.