[Static Runtime] Moved NNC operator definitions to separate files. (#63838)

[Static Runtime] Moved NNC operator definitions to separate files. (#63838)

Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/63838

Refactored NNC operator definitions code into separate files.

Made `TEWrapper` a class with a fixed set of methods and added separate definitions for them based on `TORCH_ENABLE_LLVM` to keep the same functionality as before.

Test Plan: Build and ran Static Runtime tests.

Reviewed By: hlu1

Differential Revision: D30405467

fbshipit-source-id: 606ef852bb820d5e23a0f8af1bf5dc122e90bceb