[temp.type] Do not refer to operator==, which excludes built-in ==.

Author: jensmaurer

source/templates.tex

@@ -1944,7 +1944,7 @@
 have the same type and value
 after conversion to the type of the \grammarterm{template-parameter},
 where they are considered to have the same value if they compare equal
-with \tcode{operator==}, and}
+with the \tcode{==} operator\iref{expr.eq}, and}
 \item {their corresponding template \grammarterm{template-argument}{s} refer
 to the same template.}
 \end{itemize}