Fix type-o found by Justin Hibbits

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@131346 91177308-0d34-0410-b5e6-96231b3b80d8

include/type_traits

@@ -2489,7 +2489,7 @@ template <class _Tp> struct _LIBCPP_VISIBLE is_trivial
     : public integral_constant<bool, __is_trivial(_Tp)>
 #else
     : integral_constant<bool, is_trivially_copyable<_Tp>::value &&
-                           is_trivially_default_constructible<T>::value>::value>
+                         is_trivially_default_constructible<_Tp>::value>::value>
 #endif
     {};