Adapt to the new 'activate' syntax

cython/main.pyx

@@ -110,7 +110,7 @@ cdef cypclass DirNode(Node) nolock:
         self.format_node()
 
         for child in self.children:
-            child.__activate__().build_node(NULL, dev_whitelist, ignore_paths)
+            activate(child).build_node(NULL, dev_whitelist, ignore_paths)
 
     void write_node(self, FILE * stream):
         fwrite(self.formatted.data(), 1, self.formatted.size(), stream)
@@ -267,7 +267,7 @@ cdef int start(string path) nogil:
     if node is NULL:
         return -1
 
-    node.__activate__().build_node(NULL, dev_whitelist, ignore_paths)
+    activate(node).build_node(NULL, dev_whitelist, ignore_paths)
 
     scheduler.finish()