[XS] Change in coreboot[main]: payload/external/edk2: Explicitly define the build arch

[Benjamin Doron (Code Review)]

Attention is currently required from: Arthur Heymans, Arthur Heymans, Martin L Roth, Matt DeVillier, Nicholas Sudsgaard, Sean Rhodes.

Benjamin Doron has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/80883?usp=email )

Change subject: payload/external/edk2: Explicitly define the build arch
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Patch Set 3:

(1 comment)

Patchset:

PS1:
> It's just what its built on that matter, not what for. […]

The architecture argument - `-a` - needs be `-a IA32 -a X64` so that the entrypoint is built as 32-bit code. UPL's build script might remap `-D BUILD_ARCH=X64` to this for us, I haven't looked recently.

In general, yeah, it might be good to make the build string more generic: Unless the program runner can handle mode switches, then we can make `-a IA32` conditional on ARCH_RAMSTAGE_X86_32.