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

[Nicholas Sudsgaard (Code Review)]

Attention is currently required from: Benjamin Doron, Lean Sheng Tan, Martin L Roth, Matt DeVillier, Sean Rhodes, Stefan Reinauer.

Nicholas Sudsgaard 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 2:

(1 comment)

Patchset:

PS1:
> if this breaks building UniversalPayload for Sean, then perhaps this addition needs to be moved insi […]

The directory indeed seems to be the issue:
```
make[2]: Entering directory '/home/nicholas/Development/coreboot/payloads/external/edk2/workspace/Build/UefiPayloadPkg$(BUILD_ARCH)/RELEASE_COREBOOT/X64/MdeModulePkg/Library/ImagePropertiesRecordLib/ImagePropertiesRecordLib'
GNUmakefile:281: /home/nicholas/Development/coreboot/payloads/external/edk2/workspace/Build/UefiPayloadPkg/RELEASE_COREBOOT/X64/MdeModulePkg/Library/ImagePropertiesRecordLib/ImagePropertiesRecordLib/deps_target: No such file or directory
```

I'm not sure what the `EDK2_PAYLOAD_UEFIPAYLOAD` guard is. Placing it inside a `EDK2_REPO_OFFICIAL` guard seems to work though.
```
ifeq ($(CONFIG_EDK2_REPO_OFFICIAL),y)
BUILD_STR += -D BUILD_ARCH=X64
endif

```