ieee802154: Use '%Zu' printf format for size_t.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ieee802154/raw.c b/net/ieee802154/raw.c
index 8b892e0..fca44d5 100644
--- a/net/ieee802154/raw.c
+++ b/net/ieee802154/raw.c
@@ -132,7 +132,7 @@
 	pr_debug("name = %s, mtu = %u\n", dev->name, mtu);
 
 	if (size > mtu) {
-		pr_debug("size = %u, mtu = %u\n", size, mtu);
+		pr_debug("size = %Zu, mtu = %u\n", size, mtu);
 		err = -EINVAL;
 		goto out_dev;
 	}