[NNC] Make normalization transformation in-place (#56158)
Summary:
Partially fixes https://github.com/pytorch/pytorch/issues/56157
This PR changes `normalize` API in `LoopNest` to transform the given `For` statement and not create a new one.
New API:
```
static bool normalize(For* f);
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/56158
Reviewed By: agolynski
Differential Revision: D27798361
Pulled By: navahgar
fbshipit-source-id: 57626a5a367bdf94a0efbd9dc8538f5e4e410d6b
