tests: Make dbus_p2p_group_termination_by_go more robust

Set peer_group_removed only if peer_group_added has already been set.
This fixes an issue where a propertiesChanged event triggered by an
earlier test case was able to get dbus_p2p_group_termination_by_go
terminated too early. This happened, e.g., with sequence
"dbus_p2p_two_groups dbus_p2p_group_termination_by_go".

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

tests/hwsim/test_dbus.py

@@ -4237,7 +4237,7 @@ def test_dbus_p2p_group_termination_by_go(dev, apdev):
                 return
             if len(changed_properties["Groups"]) > 0:
                 self.peer_group_added = True
-            if len(changed_properties["Groups"]) == 0:
+            if len(changed_properties["Groups"]) == 0 and self.peer_group_added:
                 self.peer_group_removed = True
                 self.loop.quit()