Use blockLevel<MatrixType>() instead of deprecated MatrixType::blocklevel

dune/solvers/iterationsteps/truncatedblockgsstep.hh

@@ -42,7 +42,7 @@ public:
     //! Perform one iteration
     virtual void iterate()
     {
-        TruncatedBlockGSStepNS::RecursiveGSStep<MatrixType::blocklevel>::apply(*this->mat_, *this->rhs_, this->ignore(), *this->x_, innerLoops_);
+        TruncatedBlockGSStepNS::RecursiveGSStep<Dune::blockLevel<MatrixType>()>::apply(*this->mat_, *this->rhs_, this->ignore(), *this->x_, innerLoops_);
     }
 
 protected: