[quant][graphmode][fx] Add support for additional_fuse_method_mapping (#46345)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/46345
Allow user to add more fusion mappings
Test Plan: Imported from OSS
Reviewed By: vkuzo
Differential Revision: D24317439
fbshipit-source-id: 3b144bbc305e41efbdf3e9fb25dbbeaad9e86c6a
