[quant][graphmode][fx] Add support for dynamic quant for RNN and RNNCell (#49126)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/49126
Test Plan:
python test/test_quantization.py TestQuantizeFxOps.test_rnn
python test/test_quantization.py TestQuantizeFxOps.test_rnn_cell
Imported from OSS
Reviewed By: raghuramank100
Differential Revision: D25449047
fbshipit-source-id: 532bf9ad2839958dde8c6f2d9399fac96b2b8bd4
