bug in CTP/simulation/src/Digitizer.cxx

in AliceO2/Detectors/CTP/simulation/src/Digitizer.cxx. 
lines 47-51:
```
case o2::detectors::DetID::FV0: {
          std::bitset<CTP_NINPUTS> inpmask = std::bitset<CTP_NINPUTS>(
            (inp->mInputsMask & CTP_INPUTMASK_FT0.second).to_ullong());
          inpmaskcoll |= inpmask << CTP_INPUTMASK_FT0.first;
          break;
```
change FT0 to FV0 in FT0.second and in FT0.first