[quant] Enable per-channel quantization for LSTM Modules (#39666)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/39666
Test Plan:
python test/test_quantization.py TestPostTrainingDynamic.test_per_channel_lstm_quantize
Imported from OSS
Differential Revision: D21977601
fbshipit-source-id: 1333259e75782e54864ab444e05397b86cd9b9aa
