graph mode: add hardswish inplace handling (#40284)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/40284
Adds graph mode handling for inplace hardswish, and test coverage for functional hardswish.
Test Plan:
```
python test/test_quantization.py TestQuantizeScriptPTSQOps.test_hardswish
```
Imported from OSS
Differential Revision: D22140628
fbshipit-source-id: 55a514f7dc1130d510f69ee4e611d7cb5e08d02e
