[CUDA] Change __CUDACC__ definition to 1 (#189457)
I recently encountered an issue where `nccl` used `#if __CUDACC__` ,
assuming `__CUDACC__` is not only defined but having a #if-able value.
https://github.com/NVIDIA/nccl/blob/v2.28.3-1/src/include/nccl_device/coop.h#L18
Looking at nvcc invocation, I see that:
```
echo "" | nvcc -x cu -E -Xcompiler -dM - | grep __CUDACC__
#define __CUDACC__ 1
```
Changing __CUDACC__ to 1 to match what NVIDIA downstream code
assumptions.
