AK: Allow printing wide characters using %ls modifier

Author: https://github.com/safarp
Commit: 704e1d13f4
Pull-request: https://github.com/SerenityOS/serenity/pull/13151
Reviewed-by: https://github.com/alimpfard ✅

Userland/Utilities/printf.cpp

@@ -118,6 +118,17 @@ struct ArgvNextArgument<const char*, V> {
     }
 };
 
+template<typename V>
+struct ArgvNextArgument<const wchar_t*, V> {
+    ALWAYS_INLINE const wchar_t* operator()(V arg) const
+    {
+        if (arg.argc == 0)
+            return L"";
+
+        return L"";
+    }
+};
+
 template<typename V>
 struct ArgvNextArgument<int, V> {
     ALWAYS_INLINE int operator()(V arg) const