RecoTauTag/RecoTau: clean -Wunused-function warnings

Clean up `-Wunused-function` warnings in GCC 4.9.0 IB: https://cmssdt.cern.ch/SDT/cgi-bin/buildlogs/slc6_amd64_gcc490/CMSSW_7_1_X_2014-02-20-0200/RecoTauTag/RecoTau

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>