I'm preparing for a #hdf5 sprint to meet 1.14 merge window for #H5Dchunk_iter consistency. This function allows you to efficiently iterate through chunk information such as the chunk address and compression filter state.

PR approved. Backporting to 1.12 required.
https://github.com/HDFGroup/hdf5/pull/2074

I might even try backporting to 1.10.
https://forum.hdfgroup.org/t/backporting-h5dchunk-iter-to-1-12-and-1-10/9971