Adjust unsupported C++ versions in some tests
Summary:
Some tests (mainly the new C++20 calendar library) fail when libc++ is
tested with '--param=std=c++98'. The failures happen because the tests
actually don't support C++98, but don't mention C++98 in the
'UNSUPPORTED:' line.
This change fixes the issue.
Reviewers: mclow.lists, ldionne
Reviewed By: ldionne
Subscribers: arphaman, michaelplatings, libcxx-commits
Differential Revision: https://reviews.llvm.org/D53640
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@345148 91177308-0d34-0410-b5e6-96231b3b80d8