fix some bug found using

make headercheck SILENT=1 CXXFLAGS="-Wall -pedantic":
* remove spurious ';'

[[Imported from SVN: r970]]

istl/mpitraits.hh

@@ -41,7 +41,7 @@ namespace Dune
     static inline MPI_Datatype getType(){ \
       return m; \
     } \
-  };
+  }
 
   ComposeMPITraits(char, MPI_CHAR);
   ComposeMPITraits(unsigned char,MPI_UNSIGNED_CHAR);