tl: fix incorrect comment about {r} vs. cl(r)

Fixes #242.

* doc/tl/tl.tex: Remove incorrect claim that {r} does not match the
PSL semantics.

doc/tl/tl.tex

@@ -867,13 +867,6 @@ is not a model of \samp{$\sere{a\PLUS{}\CONCAT\NOT
     a\CONCAT(a\STAR{}\ANDALT(a\STAR{}\CONCAT\NOT a\CONCAT
     a\STAR{}))}$} because this SERE does not accept any word.
 
-Note that the semantics of $\sere{r}$ comes from the
-$\mathsf{cl}(\cdot)$ operator defined by~\citet{dax.09.atva}.  This
-differs from the interpretation of a SERE $r$ in the context of a
-temporal formula given by the PSL standard~\citep[Appendix~B.3.1.1.2,
-item~7]{psl.04.lrm}: the $\sere{r}$ semantics used here corresponds to
-$r!\lor r$ in the PSL standard.
-
 \subsection{Syntactic Sugar}\label{sec:pslsugar}
 
 The syntax on the left is equivalent to the syntax on the right.