gluon-core: remove default bridge devices

package/gluon-core/luasrc/lib/gluon/upgrade/020-interfaces

@@ -73,4 +73,11 @@ end
 uci:delete('network', 'lan')
 uci:delete('network', 'wan')
 
+uci:foreach('network', 'device', function(dev)
+	if dev['type'] ~= 'bridge' then return end
+	if dev['ifname'] ~= 'lan' and dev['ifname'] ~= 'wan' then return end
+
+	uci:delete('network', dev['.name'])
+end)
+
 uci:save('network')