AVX512-VP2INTERSECT implementations

[vertexclique]

Currently, these implementations aren't finished. Link representations for N x i1 for llvm needs to be incorporated into the compiler. The best way to do the i1 linking is using the proc macro attribute on extern to make linking explicit to i1 representations.

Note that bool is still i8 representation from the rust's side with zero extend. That hasn't been solved for linking to llvm.

Relates to #989 and rust-lang/rust#81552

[rust-highfive]

r? @Amanieu

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[vertexclique]

we have talked with @Amanieu about it. This can wait until we land the i1 linking in the compiler.