[composite compliance] Fix a bunch of fft backwards
Replaced `at::zeros(..., grad.options()).slice().copy_(grad))`
with `grad.new_zeros(..., grad.options()).slice().copy_(grad))`
Test Plan:
- run tests
Pull Request resolved: https://github.com/pytorch/pytorch/pull/76573
Approved by: https://github.com/ngimel, https://github.com/albanD
