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

[Felix Singer (Code Review)]

Attention is currently required from: Angel Pons, Arthur Heymans, Christian Walter, David Milosevic, Julius Werner, Lean Sheng Tan, Martin L Roth, Maximilian Brune, Nico Huber.

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

The change is no longer submittable: All-Comments-Resolved is unsatisfied now.

Change subject: arch/arm64: Add EL1/EL2/EL3 support for arm64
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Patch Set 17:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/74798/comment/63ac9f5f_97ea82f1 :
PS5, Line 11: one boots into TF-A first and drops into EL2 for coreboot afterwards.
> As per the agreement in the leadership meeting, will get this patch merged once the new LBBR spec wi […]

Then let's keep this thread unresolved until this is done.