[Bazel] Build `ATen_CPU_AVX2` lib with AVX2 arch flags enabled (#37381)
Summary:
Make sleef dependency public so that `ATen_CPU_{capability}` libs can depend on it
Pull Request resolved: https://github.com/pytorch/pytorch/pull/37381
Test Plan: CI
Differential Revision: D21273443
Pulled By: malfet
fbshipit-source-id: 7f756c7f3c605e51cf0c27ea37f687913cd48708