[Quantization] import torch.fx only if torch.__version__ >= 1.8

wanchen.swc

2023-03-30 0438b966d6d9ef89fdd7a8d112d6e03b34122b1e

 .gitignore

@@ -7,4 +7,6 @@
init_model/
*.tar.gz
test_local/
RapidASR
RapidASR
export/*
*.pyc