Update kernels for non-fatal (part 18) (#2118)

Summary:
Pull Request resolved: https://github.com/pytorch/executorch/pull/2118

Update kernels and tests starting with 'u'.

Note to reviewers: Because the changeset for non-fatal touches so many files, I've split into a number of diffs. The tests will not all pass until the final diff, given that non-fatal tests are switched on in the first diff but tests are not updated until the respective later diff. See revision 6.6 of D53251417 to observe the full change-set passing CI.

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Reviewed By: manuelcandales

Differential Revision: D54182574

fbshipit-source-id: 7cedecc113fb7cc931251616e35bab161369b886