Use strong-typed enum for chroma format

source/App/DecoderApp/DecApp.cpp

source/App/EncoderApp/EncApp.cpp

source/App/EncoderApp/EncApp.h

source/App/EncoderApp/EncAppCfg.cpp

source/App/EncoderApp/EncAppCfg.h

source/App/EncoderApp/encmain.cpp

source/Lib/CommonLib/AdaptiveLoopFilter.cpp

source/Lib/CommonLib/Buffer.cpp

source/Lib/CommonLib/Buffer.h

source/Lib/CommonLib/ChromaFormat.h

source/Lib/CommonLib/CodingStructure.cpp

source/Lib/CommonLib/CodingStructure.h

source/Lib/CommonLib/ConstraintInfo.h

source/Lib/CommonLib/DeblockingFilter.cpp

source/Lib/CommonLib/Hash.cpp

source/Lib/CommonLib/IbcHashMap.cpp

source/Lib/CommonLib/InterPrediction.cpp

source/Lib/CommonLib/InterPrediction.h

source/Lib/CommonLib/IntraPrediction.cpp

source/Lib/CommonLib/IntraPrediction.h