HP aCC: record compiler flag for Ansi C++98 support for version 3.80 onwards

Old versions of aCC need a special compiler flag to get full C++98 template
support as e.g. CMake itself or the Complex and ComplexOneConfig tests need.
The same versions need a special flag to get a proper C++ library, too.
Merge topic 'hp-cpp98-tests' into next

b0f277db HP aCC: record compiler flag for Ansi C++98 support for version 3.80 onwards