BLI: move CPPType to blenlib

For more detail about `CPPType`, see `BLI_cpp_type.hh` and D14367.

Differential Revision: https://developer.blender.org/D14367

source/blender/nodes/NOD_geometry_exec.hh

@@ -32,7 +32,6 @@ using bke::ReadAttributeLookup;
 using bke::StrongAnonymousAttributeID;
 using bke::WeakAnonymousAttributeID;
 using bke::WriteAttributeLookup;
-using fn::CPPType;
 using fn::Field;
 using fn::FieldContext;
 using fn::FieldEvaluator;