refine timings for petsc cg

src/hyteg/petsc/PETScCGSolver.hpp

@@ -118,7 +118,9 @@ class PETScCGSolver : public Solver< OperatorType >
       KSPGetPC( ksp, &pc );
       PCSetType( pc, PCJACOBI );
 
+      x.getStorage()->getTimingTree()->start( "PETSc CG Solver Apply" );
       KSPSolve( ksp, bVec.get(), xVec.get() );
+      x.getStorage()->getTimingTree()->stop( "PETSc CG Solver Apply" );
 
       xVec.createFunctionFromVector( x, num, level, flag_ );