This makes it a bit simpler to remove this interface for v2 plugins
and not break external projects (libnetwork and swarmkit).
Note that before we remove the `Client()` interface from `CompatPlugin`
libnetwork and swarmkit must be updated to explicitly check for the v1
client interface as is done int his PR.
This is just a minor tweak that I realized is needed after trying to
implement the needed changes on libnetwork.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: 7c77df8acc597cd4f540d873de5fe53a3d414ba9
Component: engine
285424548c