[dtensor][6/N] change to a better/safer op registration (#90735)
This PR changes the op registration to a better mechanism, now
we require the directly overload registration instead of the op
key str, this have several benefits:
1. We ensure that the op registration registers the correct op, which
means it would be faild if the op registration become wrong (this PR
already fixing several op registration errors as we use direct
OpOverload registration
2. If the overload name get changed/deleted, we immediately know it at
the source code compilation level, which is safer
3. This also keep it consistents with the op registration mechanism with
other tensor subclasses within PyTorch
Differential Revision: [D42876250](https://our.internmc.facebook.com/intern/diff/D42876250)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/90735
Approved by: https://github.com/XilunWu, https://github.com/fduwjj
