Add Div reference (#77936)
Add Prims:
- trunc
- Replace _wrap_scalar with scalar_tensor
Add Reference:
- copysign
- div
- floor_divide
- trunc_divide
Other:
* Add support for `variant_test_name` in _find_referenced_opinfo
Pull Request resolved: https://github.com/pytorch/pytorch/pull/77936
Approved by: https://github.com/mruberry
