Fix some partial overloaded virtual functions

CHANGELOG.md

library/LocalRegions/NodalTriExp.h

library/LocalRegions/SegExp.cpp

library/LocalRegions/SegExp.h

library/MultiRegions/AssemblyMap/AssemblyMap.cpp

library/MultiRegions/AssemblyMap/AssemblyMap.h

library/MultiRegions/AssemblyMap/AssemblyMapCG.cpp

library/MultiRegions/AssemblyMap/AssemblyMapCG.h

library/MultiRegions/AssemblyMap/AssemblyMapDG.cpp

library/MultiRegions/AssemblyMap/AssemblyMapDG.h

library/StdRegions/StdSegExp.cpp

library/StdRegions/StdSegExp.h