dirstate: use `tracked` property in `_addpath`

It is semantically better.

Differential Revision: https://phab.mercurial-scm.org/D11422

mercurial/dirstate.py

@@ -674,7 +674,7 b' class dirstate(object):'
         possibly_dirty=False,
     ):
         entry = self._map.get(f)
-        if added or entry is not None and entry.removed:
+        if added or entry is not None and not entry.tracked:
             self._check_new_tracked_filename(f)
         self._dirty = True
         self._updatedfiles.add(f)