Fix aliasing violation in t-SNE

[zbjornson]

Undefined behavior introduced in #4208. These parameters are restrict-qualified, but the callers pass pointers with the same address and the arrays are modified through both pointers.

[GPUtester]

Can one of the admins verify this patch?

[dantegd]

add to allowlist

[dantegd]

@zbjornson there seem to be some clang-format minor issue after the change, you can check and solve it locally with (taken from CI logs):

utils.cuh failed! 'diff cpp/src/tsne/utils.cuh /tmp/tmp0e3j_bc3/cpp/src/tsne/utils.cuh' will show formatting violations!
clang-format failed! You have 2 options:
 1. Look at formatting differences above and fix them manually
 2. Or run the below command to bulk-fix all these at once
Bulk-fix command: 
  python cpp/scripts/run-clang-format.py  -inplace

Thanks for the patch!

[cjnolet]

LGTM

[codecov-commenter]

Codecov Report

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@@               Coverage Diff               @@
##             branch-21.12    #4363   +/-   ##
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  Hits                    ?    16009           
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[dantegd]

@gpucibot merge