Cobra's context should never be nil

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

cmd/docker/docker.go

@@ -81,10 +81,6 @@ func newDockerCommand(dockerCli *command.DockerCli) *cli.TopLevelCommand {
 	cmd.SetOut(dockerCli.Out())
 	cmd.SetErr(dockerCli.Err())
 
-	// Cobra's context may be nil in some cases, so initialize it here.
-	ctx := context.TODO()
-	cmd.SetContext(ctx)
-
 	opts, helpCmd = cli.SetupRootCommand(cmd)
 	registerCompletionFuncForGlobalFlags(dockerCli, cmd)
 	cmd.Flags().BoolP("version", "v", false, "Print version information and quit")