ar71xx: fix lan ports on ens202ext

In the stock firmware both eth0 and eth1 are set to br-lan,
add this behavior to our images.

Fixes: FS#1084

Signed-off-by: Marty E. Plummer <hanetzer@protonmail.com>

target/linux/ar71xx/base-files/etc/board.d/02_network

@@ -176,6 +176,7 @@ ar71xx_setup_interfaces()
 	all0315n|\
 	dlan-hotspot|\
 	dlan-pro-500-wp|\
+	ens202ext|\
 	ja76pf2|\
 	rocket-m-ti|\
 	ubnt-unifi-outdoor)