Backport of #20325

Contribution description

For the release tests we decided to randomize the PAN ID to not interfere with ongoing RIOT-based experiments in the testbed (see RIOT-OS/Release-Specs#300). However, lwIP currently does not include the Makefile to set the PAN ID at compile time. This fixes that.

Testing procedure

Apply the following patch

diff --git a/drivers/netdev/ieee802154.c b/drivers/netdev/ieee802154.c
index cf5a39d4b4..9068a1e8fa 100644
--- a/drivers/netdev/ieee802154.c
+++ b/drivers/netdev/ieee802154.c
@@ -44,6 +44,7 @@ void netdev_ieee802154_reset(netdev_ieee802154_t *dev)
 
     /* Initialize PAN ID and call netdev::set to propagate it */
     dev->pan = CONFIG_IEEE802154_DEFAULT_PANID;
+    printf("PANID: 0x%04x\n", dev->pan);
     dev->netdev.driver->set(&dev->netdev, NETOPT_NID, &dev->pan, sizeof(dev->pan));
 
 #if IS_USED(MODULE_IEEE802154_SECURITY)

Then compile and flash tests/pkg/lwip to a board that has an IEEE 802.15.4 radio. Open a terminal and reboot. The node should now print PANID: 0x0023. If you then recompile and flash tests/pkg/lwip with DEFAULT_PAN_ID set to another value in the environment variables, e.g. DEFAULT_PAN_ID=0x1234, without this PR, the output will still be PANID: 0x0023, with this PR it will be PANID: 0x1234.

Issues/PRs references

Required for RIOT-OS/Release-Specs#300.