LWG3042 is_literal_type_v should be inline

Author: Dawn Perchik

source/future.tex

@@ -2159,7 +2159,7 @@
 \begin{codeblock}
 namespace std {
   template<class T> struct is_literal_type;
-  template<class T> constexpr bool is_literal_type_v = is_literal_type<T>::value;
+  template<class T> inline constexpr bool is_literal_type_v = is_literal_type<T>::value;
 
   template<class> struct result_of;    // not defined
   template<class Fn, class... ArgTypes> struct result_of<Fn(ArgTypes...)>;