Revert "[inductor] Add ir.Scan and lower aten.cumsum on CUDA (#106581)"
This reverts commit 53a27021c59f1df640cba88bb48f67ee977e07f8.
Reverted https://github.com/pytorch/pytorch/pull/106581 on behalf of https://github.com/atalman due to Sorry for reverting your change, but it broke rocm CI ([comment](https://github.com/pytorch/pytorch/pull/106581#issuecomment-1710776610))
