BIM: fix setting of self.Type

Fixes #21364.

`self.Type` should be set in `__init__` and `loads`, and not in `onDocumentRestored`.

Additionally:
fixed mistake in `loads` in ifc_objects.py.

src/Mod/BIM/ArchBuilding.py

@@ -275,6 +275,7 @@ class _Building(ArchFloor._Floor):
     def __init__(self,obj):
 
         ArchFloor._Floor.__init__(self,obj)
+        self.Type = "Building"
         self.setProperties(obj)
         obj.IfcType = "Building"
 
@@ -285,13 +286,16 @@ class _Building(ArchFloor._Floor):
             obj.addProperty("App::PropertyEnumeration","BuildingType","Arch",QT_TRANSLATE_NOOP("App::Property","The type of this building"), locked=True)
             obj.BuildingType = BuildingTypes
         obj.setEditorMode('Height',2)
-        self.Type = "Building"
 
     def onDocumentRestored(self,obj):
 
         ArchFloor._Floor.onDocumentRestored(self,obj)
         self.setProperties(obj)
 
+    def loads(self,state):
+
+        self.Type = "Building"
+
 
 class _ViewProviderBuilding(ArchFloor._ViewProviderFloor):