[temp.class.spec.mfunc] Add missing comment to example

Author: tkoeppe

source/templates.tex

@@ -2484,11 +2484,12 @@
 \begin{example}
 
 \begin{codeblock}
-// primary template
+// primary class template
 template<class T, int I> struct A {
   void f();
 };
 
+// member of primary class template
 template<class T, int I> void A<T,I>::f() { }
 
 // class template partial specialization