Revert "Quant: add weight int4pack mm kernel (#110914)"
This reverts commit 9980876cab9dcedce7d7dd1c8a2e168b548eaa36.
Reverted https://github.com/pytorch/pytorch/pull/110914 on behalf of https://github.com/jeanschmidt due to Breaking internal builds ([comment](https://github.com/pytorch/pytorch/pull/110914#issuecomment-1765302621))
