jetSpectraCharged: fix matched histogram eta selection so that one can get efficiency with eta sel only on mcp jet, and purity with eta sel only on mcd jet

- checkLeadConstituentPtForMcpJets now applies to max pt of lead track
- pTHatMaxMCD was used in place of pTHatMaxMCP in some places
- fix matched hist names in rhoareasubtracted case to fit in convention used in rest of file

Author: aimeric-landou