Fix method istl_assign_to_fmatrix(). It should now assign to a DenseMatrix...

Fix method istl_assign_to_fmatrix().  It should now assign to a DenseMatrix instead of a FieldMatrix

[[Imported from SVN: r1331]]

dune/istl/scaledidmatrix.hh

@@ -455,8 +455,8 @@ namespace Dune {
 
   };
 
-  template<class K, int n>
-  void istl_assign_to_fmatrix(FieldMatrix<K,n,n>& fm, const ScaledIdentityMatrix<K,n>& s)
+  template<class M, class K, int n>
+  void istl_assign_to_fmatrix(DenseMatrix<M>& fm, const ScaledIdentityMatrix<K,n>& s)
   {
     fm = K();
     for(int i=0; i<n; ++i)