GCC 12 defaults to C++17 which removes (not just deprecates)
std::auto_ptr<>. Trying to use CXXSTD of c++03 doesn't work with
libc++ headers, but c++11 does.
Reviewed by: brooks, imp, emaste
Differential Revision: https://reviews.freebsd.org/D37531
It is added an INTERNALLIB and not installed. It will be used by kyua.
This is a preparatory commit for D24103.
Reviewed by: emaste
Obtained from: CheriBSD
Sponsored by: DARPA