deprecate docker buildx install and docker buildx uninstall

Deprecate these commands in favor of using `docker buildx` directly,
without relying on the `docker builder` alias.

The commands have been hidden since the beginning.

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

commands/install.go

@@ -47,6 +47,7 @@ func installCmd(dockerCli command.Cli) *cobra.Command {
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return runInstall(dockerCli, options)
 		},
+		Deprecated:            "use 'docker buildx' directly, without relying on the 'docker builder' alias",
 		Hidden:                true,
 		ValidArgsFunction:     completion.Disable,
 		DisableFlagsInUseLine: true,

commands/uninstall.go

@@ -53,6 +53,7 @@ func uninstallCmd(dockerCli command.Cli) *cobra.Command {
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return runUninstall(dockerCli, options)
 		},
+		Deprecated:            "use 'docker buildx' directly, without relying on the 'docker builder' alias",
 		Hidden:                true,
 		ValidArgsFunction:     completion.Disable,
 		DisableFlagsInUseLine: true,