[libc++] Add a libc++ configuration that does not support localization

When porting libc++ to embedded systems, it can be useful to drop support
for localization, which these systems don't implement or care about.

Differential Revision: https://reviews.llvm.org/D90072

libcxx/test/std/thread/thread.threads/thread.thread.class/thread.thread.id/stream.pass.cpp

@@ -5,8 +5,9 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+
 // UNSUPPORTED: libcpp-has-no-threads
+// UNSUPPORTED: libcpp-has-no-localization
 
 // <thread>