Change in coreboot[master]: payloads: Add UefiPayload support to ARM64 platforms

[Rex-BC Chen (Code Review)]

Attention is currently required from: Hung-Te Lin, Martin Roth, Paul Menzel, Julius Werner, Marty E. Plummer.
Rex-BC Chen has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/58054 )

Change subject: payloads: Add UefiPayload support to ARM64 platforms
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Patch Set 7:

(1 comment)

Patchset:

PS6:
> > modify sys-boot/edk2/edk2-9999.ebuild for this. […]

I have encounter this error:
cros/src/third_party/coreboot$ make -j

toolchain.inc:166: The coreboot toolchain for 'arm64' architecture was not found.
toolchain.inc:176: The coreboot toolchain version of iasl '20210331' was not found
toolchain.inc:202:
toolchain.inc:203: To build the entire coreboot toolchain: run 'make crossgcc'
toolchain.inc:205: To build just IASL: run 'make iasl'
toolchain.inc:207: For more toolchain build targets: run 'make help_toolchain'
toolchain.inc:208:
toolchain.inc:210: To try to use any toolchain in your path, run 'make menuconfig', then select
toolchain.inc:212: the config option: 'General setup', and 'Allow building with any toolchain'
toolchain.inc:214: Note that this is NOT supported. Using it means you're on your own.
toolchain.inc:216:
toolchain.inc:218: *** Halting the build.  Stop.