Fix documentation

luamml.dtx

@@ -242,6 +242,7 @@
 }
 %</luatex>
 %    \end{macrocode}
+% \end{macro}
 %
 % \begin{macro}{\luamml_begin_single_file:, \luamml_end_single_file:}
 %   Everything between these two commands gets written into the same XML file.
@@ -433,6 +434,7 @@
 }
 %</pdftex>
 %    \end{macrocode}
+% \end{macro}
 %
 %
 % \subsection{Patching}