Fix for normalizing signature for op overloads (#77182)
Previously, we were taking the `.op` from OpOverload/OpOverloadPacket and looking for a mapping in `_jit_builtins` for their signature. Those will only exist for operators on the public api, not the overload packets, e.g. `torch.resize_as_` not `torch.ops.aten.resize_as_` (as least in this case, and im pretty sure generally). The OpOverloads/OpOverloadPackets have schemas stored on them so we can just use those directly.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/77182
Approved by: https://github.com/anjali411
