[XS] Change in coreboot[main]: arch/arm64: Add Clang as supported target

[Arthur Heymans (Code Review)]

Attention is currently required from: Jon Murphy, Julius Werner.

Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74501?usp=email )

Change subject: arch/arm64: Add Clang as supported target
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Patch Set 26:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/74501/comment/ae004968_3ca7b0b8 :
PS26, Line 13: config files to achieve the same level of build testing.
> Can you just change the sc7180 memlayout to make a bit more space instead? You can steal a few KB from PRERAM_CBFS_CACHE if necessary.

I was just not aware of the SOC details: loading a bootblock is often soc specific with sometimes size restrictions. If you say it's possible to do so I can for sure try this.