fix repocard issues (#20)

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

util/mdns/client.go

@@ -282,7 +282,7 @@ func (c *client) Close() error {
 	return nil
 }
 
-// setInterface is used to set the query interface, uses sytem
+// setInterface is used to set the query interface, uses system
 // default if not provided
 func (c *client) setInterface(iface *net.Interface, loopback bool) error {
 	p := ipv4.NewPacketConn(c.ipv4UnicastConn)