[M] Change in coreboot[main]: arch/arm64: Add EL1/EL2/EL3 support for arm64

[Martin L Roth (Code Review)]

Attention is currently required from: Arthur Heymans, Christian Walter, David Milosevic, Julius Werner, Lean Sheng Tan, Maximilian Brune.

Martin L Roth has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74798?usp=email )

Change subject: arch/arm64: Add EL1/EL2/EL3 support for arm64
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Patch Set 6:

(1 comment)

File src/arch/arm64/Kconfig:

https://review.coreboot.org/c/coreboot/+/74798/comment/7316fa51_94058ae8 :
PS6, Line 30: 1 (EL1), 2 (EL2) and 3 (EL3)
Nit: Could you maybe define what these are or add why one would be chosen over another?

You can also add "If you don't know what this does, leave at the default." if you wanted.

If you don't think this is needed, feel free to Ack and close.