docs: add FractionalMaxPool3d in pooling layers (#52556)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/51625
Pull Request resolved: https://github.com/pytorch/pytorch/pull/52556
Reviewed By: smessmer
Differential Revision: D26593666
Pulled By: bdhirsh
fbshipit-source-id: 3d81d23fa70efa0f794dde47a34baad0aaa9c751
