qcacmn: Fix assert for flush rx ptk when vdev deleted

When vdev deleted and interface down, there are pending pkts in nbuf
queue of dp rx thread in cornel cases, when flush cmd comes, even vdev
is not found by vdev id, rx stack callback isn't set to NULL, pkts are
still delivered to kernel stack, but rx queue is invalid now, assert
will happen when GRO flush happens.
Fix by setting rx stack callback as NULL when vdev isn't found by vdev
id.

Change-Id: Iad3b71dbc86563a4f8b5369474b2a901cdf8b325
CRs-Fixed: 2995694

dp/wifi3.0/dp_main.c

@@ -8215,9 +8215,11 @@ void dp_get_os_rx_handles_from_vdev_wifi3(struct cdp_soc_t *soc_hdl,
 	struct dp_vdev *vdev = dp_vdev_get_ref_by_id(soc, vdev_id,
 						     DP_MOD_ID_CDP);
 
-	if (!vdev)
+	if (qdf_unlikely(!vdev)) {
+		*stack_fn_p = NULL;
+		*osif_vdev_p = NULL;
 		return;
-
+	}
 	*stack_fn_p = vdev->osif_rx_stack;
 	*osif_vdev_p = vdev->osif_vdev;
 	dp_vdev_unref_delete(soc, vdev, DP_MOD_ID_CDP);