Documentation of aarch64 port on Spectrum OS upstream

[Ville Ilvonen <ville.ilvonen@unikie.com>]

Hi,

We've built the wayland demo branch on aarch64 port and added some other 
apps on it to showcase embedded virtualization with Spectrum OS.

The build configuration for the reference device is documented [1] with 
the out-of-tree build configuration as agreed in our earlier 
discussion[2]. There's also some additional accompanied documentation on 
binary cache we have used with aarch64 and could be of general use. I'd 
like to see that documentation upstreamed as much as possible.

Would it make sense to link this work from Spectrum documentation? To 
indicate work in progress aarch64 support with known issues on a ref. 
device and avoid forking this documentation?

The practical benefit is that anyone interested in building Spectrum OS 
for an aarch64 device using vendor BSP would have some reference linked 
from Spectrum OS documentation - e.g. an initial porting guide as even 
the x86_64 does not yet use the build configuration. Additionally, I 
don't want to fragment Spectrum OS ports and their documentation further 
than necessary.

Best,

-Ville

[1] https://github.com/tiiuae/spectrum-config-imx8/blob/main/README.md
[2] 
https://spectrum-os.org/lists/archives/spectrum-discuss/CAP-nJwHTmROzMbyYNtrTrOdXGV-iJvwPuJ3FSZb3gLy5R3z80Q@mail.gmail.com/