Remove no-longer-used attribute

Cython/Compiler/Nodes.py

@@ -5549,8 +5549,6 @@ class CypclassWrapperDefNode(CClassDefNode):
         self.entry.type.is_cyp_wrapper = 1
         # > associate the wrapper type to the wrapped type
         self.wrapped_cypclass.entry.type.wrapper_type = self.entry.type
-        # > remember the cname of the wrapped type
-        self.entry.type.wrapped_decl = self.wrapped_cypclass.entry.type.empty_declaration_code()
 
 
 class PropertyNode(StatNode):

Cython/Compiler/PyrexTypes.py

@@ -1498,13 +1498,11 @@ class PyExtensionType(PyObjectType):
     #  defered_declarations [thunk]      Used to declare class hierarchies in order
     #  check_size       'warn', 'error', 'ignore'    What to do if tp_basicsize does not match
     #  is_cyp_wrapper   boolean          Whether this extension type wraps a cypclass
-    #  wrapped_decl    string or None    The declaration code of the wrapped cypclass type when this is a cyp_wrapper
 
     is_extension_type = 1
     has_attributes = 1
     early_init = 1
     is_cyp_wrapper = 0
-    wrapped_decl = None
 
     objtypedef_cname = None