rust/genprotimg: Add '--help-all' and '--help-experimental' for backward compatibility

The '--help-all' and '--help-experimental' flags are now considered
deprecated, but should still be available for backward compatibility.

Fixes: f4cf4ae6eb ("rust: Add a new tool called 'pvimg'")
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

rust/pvimg/src/cli.rs

@@ -248,6 +248,14 @@ pub struct GenprotimgCliOptions {
     // version command.
     #[arg(long, action = clap::ArgAction::SetTrue )]
     pub version: (),
+
+    #[arg(long, action = clap::ArgAction::HelpLong, hide(true))]
+    /// Print help (deprecated, use '--help' instead).
+    help_all: (),
+
+    #[arg(long, action = clap::ArgAction::HelpLong, hide(true))]
+    /// Print help (deprecated, use '--help' instead).
+    help_experimental: (),
 }
 
 impl GenprotimgCliOptions {