DNNL: fix F.max_pool2d and F.avg_pool2 issue when stride=None (#39221)
Summary:
For F.max_pool2d and F.avg_pool2d, there has **RuntimeErro**r when stride is **None**, this PR sovle it.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/39221
Differential Revision: D22059565
Pulled By: ngimel
fbshipit-source-id: 2080e1e010815aedd904c58552e92be9f7443d38
