caffe2 | added missing operator source file (#17272)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/17272
after windows-specific fixes were applied new file was left out of CMakeLists
Reviewed By: orionr
Differential Revision: D14140419
fbshipit-source-id: 6a6c652048ed196ec20241bc2a1d08cbe2a4e155
