Revert "[Compiled Autograd] Move to torch::dynamo::autograd namespace (#105854)"
This reverts commit 26e3b4020f01d4fc2b7f63e1de4c94d2c8b362b5.
Reverted https://github.com/pytorch/pytorch/pull/105854 on behalf of https://github.com/PaliC due to breaking internal embedded device tests (details shared with author) ([comment](https://github.com/pytorch/pytorch/pull/105854#issuecomment-1650559375))
