fix compilation with clang++-3.6 -Wdocumentation

* src/tgba/tgbasafracomplement.cc: Remove documentation of inexisting
argument.
* src/tgbaalgos/hoaf.hh: Fix typo in documentation.

src/tgba/tgbasafracomplement.cc

@@ -1142,9 +1142,6 @@ namespace spot
   ///   series        = {Lecture Notes in Computer Science},
   ///   publisher     = {Springer-Verlag}
   /// }
-  ///
-  /// @param local_state the state from which we want to compute the successors.
-  ///
   tgba_succ_iterator*
   tgba_safra_complement::succ_iter(const state* state) const
   {

src/tgbaalgos/hoaf.hh

@@ -44,7 +44,7 @@ namespace spot
   /// \param g The automaton to output.
   /// \param f The (optional) formula associated to the automaton.  If given
   ///          it will be output as a comment.
-  /// \param a acceptance Force the type of acceptance mode used
+  /// \param acceptance Force the type of acceptance mode used
   ///         in output.
   /// \param alias Whether aliases should be used in output.
   /// \param newlines Whether to use newlines in output.