[caffe2/aten] Fix clang build (#44934)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/44934
Fix build errors when using clang to build cuda sources:
```
In file included from aten/src/ATen/native/cuda/DistributionBernoulli.cu:4:
In file included from aten/src/ATen/cuda/CUDAApplyUtils.cuh:5:
caffe2/aten/src/THC/THCAtomics.cuh:321:1: error: control reaches end of non-void function [-Werror,-Wreturn-type]
}
^
1 error generated when compiling for sm_70.
In file included from aten/src/ATen/native/cuda/DistributionBernoulli.cu:4:
In file included from aten/src/ATen/cuda/CUDAApplyUtils.cuh:5:
caffe2/aten/src/THC/THCAtomics.cuh:321:1: error: control reaches end of non-void function [-Werror,-Wreturn-type]
}
^
1 error generated when compiling for sm_60.
In file included from aten/src/ATen/native/cuda/DistributionBernoulli.cu:4:
In file included from aten/src/ATen/cuda/CUDAApplyUtils.cuh:5:
caffe2/aten/src/THC/THCAtomics.cuh:321:1: error: control reaches end of non-void function [-Werror,-Wreturn-type]
}
^
1 error generated when compiling for sm_52.
```
Test Plan: CI
Reviewed By: ngimel
Differential Revision: D23775266
fbshipit-source-id: 141e6624e2da870a8c50ff9f71fcf0717222fb17
