[caffe2] fix no return statement in constexpr function Clang error in TypeIndex.h (#33576)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/33576
`throw` statement at the end of `constexpr` is ill-formed according to Clang. It happens when Clang is driving CUDA compilation and compiles for device the effected code. Due to its compilation model it requires host code to be well-formed even when compiling for device.
Fix the error by guarding the entire definition of `type_index_impl` with `__CUDA_ARCH__` check.
Test Plan:
```lang=bash
buck build mode/opt -c fbcode.cuda_use_clang=true //fblearner/flow/projects/dper:workflow
buck build mode/opt //fblearner/flow/projects/dper:workflow
```
Execute tests on devgpu:
```
buck test mode/dev-nosan -j 8 //caffe2/caffe2/python/operator_test/... //caffe2/test:cuda
```
Reviewed By: smessmer
Differential Revision: D20008881
fbshipit-source-id: b0dc9abf0dc308b8b8637b54646a0411baf7fef3
