wgengine/router: remove unused wireguard *Device argument.

Signed-off-by: David Anderson <danderson@tailscale.com>

wgengine/router/router_freebsd.go

@@ -5,7 +5,6 @@
 package router
 
 import (
-	"github.com/tailscale/wireguard-go/device"
 	"github.com/tailscale/wireguard-go/tun"
 	"tailscale.com/types/logger"
 )
@@ -15,8 +14,8 @@ import (
 // Work is currently underway for an in-kernel FreeBSD implementation of wireguard
 // https://svnweb.freebsd.org/base?view=revision&revision=357986
 
-func newUserspaceRouter(logf logger.Logf, _ *device.Device, tundev tun.Device) (Router, error) {
-	return newUserspaceBSDRouter(logf, nil, tundev)
+func newUserspaceRouter(logf logger.Logf, tundev tun.Device) (Router, error) {
+	return newUserspaceBSDRouter(logf, tundev)
 }
 
 func cleanup(logf logger.Logf, interfaceName string) {