[libcxx] Fix the type attribute for a couple templates

Use `_LIBCPP_TEMPLATE_VIS` instead of `_LIBCPP_TYPE_VIS` for a template
class.

This fixes the nodiscard_extensions.pass.cpp and a couple
func.search.default test cases when built in MSVC/DLL configurations.

Differential Revision: https://reviews.llvm.org/D99932

GitOrigin-RevId: 948dd664c3ed30dd853df03cb931436f280bad4a
diff --git a/include/functional b/include/functional
index bbc2301..47449b7 100644
--- a/include/functional
+++ b/include/functional
@@ -3176,7 +3176,7 @@
 
 // default searcher
 template<class _ForwardIterator, class _BinaryPredicate = equal_to<>>
-class _LIBCPP_TYPE_VIS default_searcher {
+class _LIBCPP_TEMPLATE_VIS default_searcher {
 public:
     _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
     default_searcher(_ForwardIterator __f, _ForwardIterator __l,