[quant][graphmode][fix] Fold conv bn (#40865)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/40865
1. applied filter for the module types
2. removed the assumption that the conv bn are immediate child of parent module
Test Plan:
python test/test_quantization.py TestQuantizeJitPasses
Imported from OSS
Differential Revision: D22338074
fbshipit-source-id: 64739a5e56c0a74249a1dbc2c8454b88ec32aa9e
