[quant][graphmode][fx][fp16] Add fp16 support for {add|mul}{_relu} (#52714)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/52714
Test Plan:
python test/test_quantization.py TestQuantizedOps.test_add
python test/test_quantization.py TestQuantizedOps.test_mul
python test/test_quantization.py TestQuantizedOps.test_add_relu
python test/test_quantization.py TestQuantizedOps.test_mul_relu
Imported from OSS
Reviewed By: vkuzo
Differential Revision: D26626092
fbshipit-source-id: 91d040efa51e9c955eb688ec16a30f0c12233958
