dirstate-entry: use `?` for the state of entry without any tracking

This is what the dirstate use at a higher level.

Differential Revision: https://phab.mercurial-scm.org/D11525

mercurial/pure/parsers.py

@@ -306,6 +306,8 b' class DirstateItem(object):'
         dirstatev1 format. It would make sense to ultimately deprecate it in
         favor of the more "semantic" attributes.
         """
+        if not (self._p1_tracked or self._p2_tracked or self._wc_tracked):
+            return b'?'
         return self.v1_state()
 
     @property