avoid division by 0 in generate_acoustic_environments_metadata.py update_quantization_error()

def update_quantization_error(name, quantized_value, value):

    if value == 0:

        if quantized_value != 0:

            print('    {}: value = 0, quantized value = {}'.format(name, quantized_value))

    else:

        max_quantization_error[name] = max(abs(quantized_value - value) / value, max_quantization_error[name])

        if print_quantized:

            print('    {}: {}'.format(name, quantized_value))