[libc++] Remove the c++98 Lit feature from the test suite
C++98 and C++03 are effectively aliases as far as Clang is concerned.
As such, allowing both std=c++98 and std=c++03 as Lit parameters is
just slightly confusing, but provides no value. It's similar to allowing
both std=c++17 and std=c++1z, which we don't do.
This was discovered because we had an internal bot that ran the test
suite under both c++98 AND c++03 -- one of which is redundant.
Differential Revision: https://reviews.llvm.org/D80926
diff --git a/libcxx/test/std/numerics/bit/bit.pow.two/log2p1.pass.cpp b/libcxx/test/std/numerics/bit/bit.pow.two/log2p1.pass.cpp
index bf39838..de6ec3b 100644
--- a/libcxx/test/std/numerics/bit/bit.pow.two/log2p1.pass.cpp
+++ b/libcxx/test/std/numerics/bit/bit.pow.two/log2p1.pass.cpp
@@ -6,7 +6,7 @@
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
-// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
+// UNSUPPORTED: c++03, c++11, c++14, c++17
// template <class T>
// constexpr T log2p1(T x) noexcept;