[et][dim order] Makes DimOrderOpsMap as an operator to operator mapping

Pull Request resolved: https://github.com/pytorch/executorch/pull/7187

This diff updates DimOrderOpsMap from name-to-operator mapping to operator-to-operator mapping, which has multiple benefits:

1. Reduce dialect ambiguity. Different dialects op may map to same name (e.g. `aten.to_copy` and `exir_ops.edge.aten._to_copy.default`). Directly using op can diminish the ambiguity.
2. Auto-maintain MemoryFormatOpsMap by reverting DimOrderOpsMap
ghstack-source-id: 256633613
@exported-using-ghexport

Differential Revision: [D66773612](https://our.internmc.facebook.com/intern/diff/D66773612/)

Co-authored-by: gasoonjia <gasoonjia@icloud.com>