[NNC] Handle int64 indices and loop bounds (#59769)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/59769
Allow loop bound and tensor indice to be either int32 or int64, and avoid unnecessary cast op.
Test Plan:
```
build/bin/test_tensorexpr
```
Reviewed By: H-Huang
Differential Revision: D29173970
Pulled By: desertfire
fbshipit-source-id: 859a876ddb1b41535b2266089aa1222884295c78
