Revert "Move at::{Refcounted,}MapAllocator to c10 (#109881)"
This reverts commit 0341deb1c720d8c908ed40e853eaacfc8ac37181.
Reverted https://github.com/pytorch/pytorch/pull/109881 on behalf of https://github.com/albanD due to It does break buck build ([comment](https://github.com/pytorch/pytorch/pull/109881#issuecomment-1756195823))
