Fix indexing of PCA to use safer types

[lowener]

Related to #4105.

This PR fixes the types used for indexing and sizes in the PCA/TSVD C++ code.

[cjnolet]

@lowener, it would be helpful to also change the raft branch in this PR to your branch from the corresponding raft pr so we can verify the code works before merging the raft side.

[lowener]

rerun tests

[lowener]

rerun tests

[lowener]

rerun tests

[lowener]

rerun tests

[lowener]

As a note, the CI failed (after 5 hours) on a timeout on cuml.test.test_nearest_neighbors.test_ivfpq_pred[8-512-4000-True-4-32-8]: Failed: Timeout >300.0s

And a build fail with

01:14:55   conda.CondaMultiError: Downloaded bytes did not match Content-Length
01:14:55   url: https://conda.anaconda.org/nvidia/linux-64/cudatoolkit-11.0.221-h6bb024c_0.tar.bz2
01:14:55   target_path: /opt/conda/envs/rapids/pkgs/cudatoolkit-11.0.221-h6bb024c_0.tar.bz2
01:14:55   Content-Length: 999268491
01:14:55   downloaded bytes: 79332612```

[lowener]

rerun tests

[lowener]

rerun tests

[cjnolet]

We should be careful to keep the precision relevant to the upper bounds of the individual arguments. For example, arguments like n_parts and n_stream will never go beyond 32-bit so we should use an int or uint32_t there. I'm also inclined to keep the precision of loop counters relevant to the upper bounds of their types, but that's more of a nitpick on host (there's a performance impact on device).

Overall it looks great, the changes I've requested are mostly repetitive and mechanical.

I think we can keep n_components as 64-bit since its upper-bound is related to n_cols/n_rows.

[codecov-commenter]

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[cjnolet]

LGTM

[cjnolet]

@gpucibot merge

[cjnolet]

@gpucibot merge