Generalize sha2-512 zkLLVM SDK interface

[nkaskov]

We have an intrinsic for sha2-512, but its interface is very custom and it differs from the interfaces of native sha2-512. We need to either update intrinsic's interface or extend sha2-512 circuit interface with a proper intrinsic call, so it will allow us to call hash from arbitrary byte-blob (we can start with supporting std::array<std::uint, ContainerSize> hashing).