Created by: juncaipeng
- Save all input scales and quantization info in quantized op.
- Quantized ops with weight have attrs: is_quantized_with_weight, activation_bits, weight_bits, activation_quantize_type, weight_quantize_type
- For quantized ops without weight have attrs: is_quantized_without_weight, activation_bits
- All quantized ops have the input threshold (KL threshold or abs_max value), the name of input threshold is the intput var name of fake_quant/fake_quant_dequant.