Runs CUDA test_istft_of_sine on CUDA (#41523)
Summary:
The test was always running on the CPU. This actually caused it to throw an error on non-MKL builds, since the CUDA test (which ran on the CPU) tried to execute but the test requires MKL (a requirement only checked for the CPU variant of the test).
Fixes https://github.com/pytorch/pytorch/issues/41402.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/41523
Reviewed By: ngimel
Differential Revision: D22569344
Pulled By: mruberry
fbshipit-source-id: e9908c0ed4b5e7b18cc7608879c6213fbf787da2
