Name inference for softmax, log_softmax and Dimname overloads. (#24087)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/24087
Added name inference rules for softmax and log_softmax.
Added the overloads for Dimname dim to softmax and log_softmax.
Test Plan: - [namedtensor ci]
Differential Revision: D16763391
Pulled By: zou3519
fbshipit-source-id: 676a14666d42441eb7d3c9babef7461c7b78d290
