gluon-core: disable VXLAN checksums

Our VXLAN setup was changed to accept VXLAN packets without checksum almost
2 months ago, so we can disable sending the checksums now as well. Slightly
improves performance.

package/gluon-core/files/lib/netifd/proto/gluon_wired.sh

@@ -46,6 +46,7 @@ proto_gluon_wired_setup() {
                 json_add_string peer6addr 'ff02::15c'
                 json_add_int vid "$(lua -lgluon.util -e 'print(tonumber(gluon.util.domain_seed_bytes("gluon-mesh-vxlan", 3), 16))')"
                 json_add_boolean rxcsum '0'
+                json_add_boolean txcsum '0'
                 json_close_object
                 ubus call network add_dynamic "$(json_dump)"
         fi