Ex-review.2: add note that * is terminal

info/exercises/src/ex-review/ex/ll1.tex

@@ -10,6 +10,9 @@
     type &::= \lstinline|int| \mid type \lstinline|*| \\
   \end{align*}
 
+  Note that \(type\lstinline|*|\) is \(type\) followed by the terminal
+  \(\lstinline|*|\), not a Kleene star.
+
   \begin{enumerate}
     \item Compute \(\nullable\) and \(\first\) for each non-terminal of the grammar above.
     \begin{solution}