TopQuarkAnalysis/TopSkimming: add missing dependency on DataFormats/Common

The missing dependency is visible on GCC pre-4.9.0 IB: https://cmssdt.cern.ch/SDT/cgi-bin/buildlogs/slc6_amd64_gcc490/CMSSW_7_1_X_2014-02-14-0200/TopQuarkAnalysis/TopSkimming

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>