Remove unnecessary tp_flag from interpolation type

Author: lysnikolaou

Objects/interpolationobject.c

@@ -118,7 +118,7 @@ PyTypeObject _PyInterpolation_Type = {
     .tp_doc = PyDoc_STR("Interpolation object"),
     .tp_basicsize = sizeof(interpolationobject),
     .tp_itemsize = 0,
-    .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC | _Py_TPFLAGS_MATCH_SELF,
+    .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,
     .tp_new = (newfunc) interpolation_new,
     .tp_alloc = PyType_GenericAlloc,
     .tp_dealloc = (destructor) interpolation_dealloc,