Optimize __dlpack_device__ performance (#86665)
This can be critical when processing a large number of tensors
```bash
python -m timeit --setup 'import torch; t = torch.empty(1000, device="cuda")' 't.__dlpack_device__()'
```
based on 1.12.1:
before:
100000 loops, best of 5: 2.32 usec per loop
after:
500000 loops, best of 5: 844 nsec per loop
Pull Request resolved: https://github.com/pytorch/pytorch/pull/86665
Approved by: https://github.com/SunDoge, https://github.com/soulitzer
