[nnc] Fixed handling of 0-sized tensors in cat (#67734)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/67734
The implementation of `aten::cat` op in NNC has to ignore tensors that have 0-size in any dimension.
Test Plan: `buck test mode/dev-nosan //caffe2/test/cpp/tensorexpr:tensorexpr -- --exact 'caffe2/test/cpp/tensorexpr:tensorexpr - Kernel.CatWithEmptyInputs'`
Reviewed By: ZolotukhinM
Differential Revision: D32122171
fbshipit-source-id: 90c697813bc504664673cdc262df6e7ce419c655
