TrigT1CaloMonitoring+xAODTrigL1Calo: Fix clang compilation.
operator<< should be defined in the same namespace as the object that it's streaming for argument-dependent lookup to work properly.
However, operator<< should almost always be defined along with the object it's streaming.
Move operator<< definitions for CMXEtSums_v1, CMXJetHits_v1, and JEMTobRoI_v1 to xAODTrigL1Calo from TrigT1CaloMonitoring (and move them into the xAOD namespace).