Reduce to just one preprocessor macro and only do C++98 case.
Reduce to just one preprocessor macro and only do C++98 case.

kaskr/CppAD,wegamekinglc/CppAD,wegamekinglc/CppAD,kaskr/CppAD,wegamekinglc/CppAD,kaskr/CppAD,kaskr/CppAD,wegamekinglc/CppAD,kaskr/CppAD,wegamekinglc/CppAD