[nnapi] add log_softmax (#61378)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/61378
Test Plan: Imported from OSS
Reviewed By: axitkhurana
Differential Revision: D29597355
Pulled By: IvanKobzarev
fbshipit-source-id: 55124749f8eeffa2b2713f7cffd5ccf965561de1
