[PWGHF] Fix tree creator output consistency

[fchinu]

Make tree creators actually produce the pdg code of B mother instead of its flag

[github-actions]

O2 linter results: ❌ 0 errors, ⚠️ 0 warnings, 🔕 0 disabled

[alibuild]

Error while checking build/O2Physics/code-check for 3f1d315 at 2026-08-11 23:17:

## sw/BUILD/O2Physics-code-check-latest/log
--
========== List of issues found ==========
++ echo 'Found 4 errors and 0 warnings.'
Found 4 errors and 0 warnings.
++ [[ 4 -gt 0 ]]
++ cat /sw/BUILD/bd43352441fea871f677b150e719ccbfe59af9c5/O2Physics-code-check/errors.txt
PWGHF/TableProducer/treeCreatorD0ToKPi.cxx:24:1: error: included header utilsAnalysis.h is not used directly [misc-include-cleaner,-warnings-as-errors]
PWGHF/TableProducer/treeCreatorDplusToPiKPi.cxx:25:1: error: included header utilsAnalysis.h is not used directly [misc-include-cleaner,-warnings-as-errors]
PWGHF/TableProducer/treeCreatorDsToKKPi.cxx:26:1: error: included header utilsAnalysis.h is not used directly [misc-include-cleaner,-warnings-as-errors]
PWGHF/TableProducer/treeCreatorDsToKKPi.cxx:263:64: error: variable 'channelsResonant' is non-const and globally accessible, consider making it const [cppcoreguidelines-avoid-non-const-global-variables,-warnings-as-errors]
++ [[ 0 -gt 0 ]]
++ [[ 4 -gt 0 ]]
++ exit 1
--

Full log here.