engine: remove swarm/services mention for ipv6

Signed-off-by: David Karlsson <david.karlsson@docker.com>

Author: David Karlsson

config/daemon/ipv6.md

@@ -6,9 +6,9 @@ redirect_from:
 - /engine/userguide/networking/default_network/ipv6/
 ---
 
-Before you can use IPv6 in Docker containers or swarm services, you need to
+Before you can use IPv6 in Docker containers, you need to
 enable IPv6 support in the Docker daemon. Afterward, you can choose to use
-either IPv4 or IPv6 (or both) with any container, service, or network.
+either IPv4 or IPv6 (or both) with any container or network.
 
 > **Note**
 >