Replaces our built-in SHA3 implementation with a verified one from the HACL* project.
This implementation is used when OpenSSL does not provide SHA3 or is not present.
3.11 shiped with a very slow tiny sha3 implementation to get off of the <=3.10 reference implementation that wound up having serious bugs. This brings us back to a reasonably performing built-in implementation consistent with what we've just replaced our other guaranteed available standard hash algorithms with: code from the HACL* project.
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Co-authored-by: Gregory P. Smith <greg@krypto.org>
Jonathan Protzenko