DragWlToX: Do not send position before enter

According to the spec, enter has to be send before position.
Sending position first seems to confuse clients, before this
change X windows only seemed to get data when the pointer left and
entered them for a second time. Now it works straight away.
BUG:437406

src/xwl/drag_wl.cpp

@@ -392,7 +392,7 @@ void Xvisit::determineProposedAction()
         m_proposedAction = DnDAction::None;
     }
     // send updated action to X target
-    if (oldProposedAction != m_proposedAction) {
+    if (oldProposedAction != m_proposedAction && m_state.entered) {
         sendPosition(waylandServer()->seat()->pointerPos());
     }
 }