Implement meta functions for rshift and lshift (#103637)
Fixes #103606
Was using this script to exercise new code, cause I can never remember which test it is.
```
import torch
@torch.compile(fullgraph=True, dynamic=True)
def shift_right(tensor: torch.Tensor) -> torch.Tensor:
return (tensor >> 2).to(torch.long)
def main():
sample_input = torch.tensor([4, 4, 16, 32], dtype=torch.uint8)
print(shift_right(sample_input))
if __name__ == "__main__":
main()
```
And iterated through the error messages
Pull Request resolved: https://github.com/pytorch/pytorch/pull/103637
Approved by: https://github.com/ezyang
