install/uninstall: allow aliasing buildx to docker builder

Currently the user can type `docker buildx` to use this tool.
This patch allows the user to install buildx as a `docker builder` alias.

As an additional benefit, this allows the regular `docker build` to hook
into `buildx build`.

Note that the install and uninstall commands are currently hidden.

Signed-off-by: Tibor Vass <tibor@docker.com>

commands/root.go

@@ -32,6 +32,8 @@ func addCommands(cmd *cobra.Command, dockerCli command.Cli) {
 		useCmd(dockerCli),
 		inspectCmd(dockerCli),
 		stopCmd(dockerCli),
+		installCmd(dockerCli),
+		uninstallCmd(dockerCli),
 		imagetoolscmd.RootCmd(dockerCli),
 	)
 }