Add C++ implementation of histogramdd
This creates a `histogramdd` operator with overloads matching the `Union`
behaviour used in the functional variant. Moving into C++ is preferred because
it can handle torch function automatically instead of needing to differentiate
between the overloads manually.
This also adds a new return type: `std::tuple<Tensor, std::vector<Tensor>>`. For
which I've updated `wrap` to be completely generic for tuples and removed the
old manual definitions.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/74200
Approved by: https://github.com/ezyang
