This commit adds a hidden placeholder of `.Self` for
`docker node ls --format` so that if the node is the same
as the current docker daemon, then a `*` is outputed.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
Upstream-commit: 7328ae12cc3e14b3eb6ab01f09f6d94a82a44066
Component: engine