correct docu

tagpdf-backend.dtx

@@ -253,7 +253,7 @@ local tagunmarkedbool= token.create("g_@@_tagunmarked_bool")
 local truebool       = token.create("c_true_bool")
 %    \end{macrocode}
 % with this token we can query the state of the softhyphen boolean
-% and so detect if hyphens should be marked with ActualText
+% and so detect if hyphens from hyphenation should be replaced by soft-hyphens.
 %    \begin{macrocode}
 local softhyphenbool = token.create("g_@@_softhyphen_bool")
 %    \end{macrocode}