aarch64: Re-enable S3

[mastertheknife]

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Changelog category (leave one):

• Build/Testing/Packaging Improvement

Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):
Re-enable the S3 (AWS) library on aarch64
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Detailed description / Documentation draft:
This one seemed strange to me, because this is not some low-level platform library. Its a library that pretty much does REST requests.
And many of the ARM instances are on AWS, making it likely that they'll need the S3 feature.
This feature gets successfully built for ppc64le, so why not aarch64 as well?
It was disabled in the commit below with reason "ARM minimal build", but i believe this shouldn't be a minimal build anymore :)
521e2e7
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[alexey-milovidov]

Ok. Maybe it was disabled just in case. Will see.

PS. I also expect that ARM version will be popular in AWS, although it is:

• not tested in CI;
• there are known issues.

[alexey-milovidov]

Ok, it's cross-compiled successfully for AArch64.