Make ATen-cpu cuda/rocm agnostic (#121082)
Summary: This specific rocm logic will make aten-cpu code diverge between rocm and cuda. This is not good because we won't be able to share aten-cpu.so between rocm and cuda. More specifically, this will prevent us build aten-hip by default, which requires us to set up rocm specific rules which is an extra burden for our build system.
Test Plan: sandcastle + oss ci
Differential Revision: D54453492
Pull Request resolved: https://github.com/pytorch/pytorch/pull/121082
Approved by: https://github.com/jeffdaily, https://github.com/aaronenyeshi, https://github.com/albanD
