message: fix for the bug of a wrong pointer comparison
diff: @@ -899,7 +899,7 @@ Int_t AliEmbeddingEventForHFTask::CheckOrigin(AliAODMCParticle* part, TClonesArr
  while (mother >= 0) {
  istep++;
  AliAODMCParticle* mcGranma = static_cast<AliAODMCParticle*>(mcArray->At(mother));
  - if (mcGranma >= 0) {
  + if (mcGranma) {
  pdgGranma = mcGranma->GetPdgCode();
  abspdgGranma = TMath::Abs(pdgGranma);
  if ((abspdgGranma > 500 && abspdgGranma < 600) || (abspdgGranma > 5000 && abspdgGranma < 6000)) {
  @@ -948,7 +948,7 @@ Int_t AliEmbeddingEventForHFTask::CheckOrigin(Int_t ipart, AliStack* stack)
  while (mother >= 0) {
  istep++;
  TParticle* mcGranma = stack->Particle(mother);
  - if (mcGranma >= 0) {
  + if (mcGranma) {
  pdgGranma = mcGranma->GetPdgCode();
  abspdgGranma = TMath::Abs(pdgGranma);
  if ((abspdgGranma > 500 && abspdgGranma < 600) || (abspdgGranma > 5000 && abspdgGranma < 6000)) {
  