Remove useless options

[VincentLanglet]

Subject

We're setting code, name and label.

• As explained here, I think that removing code should be considered as a bugfix.
• The name option is not used.
• The label option is useless ; it's already set in the SonataAdminBundle, so the line is doing nothing.

I try it on my project and saw no impact.

Changelog

### Fixed
- Unavoidable deprecation about the `code` option.

[dmaicher]

not sure of the impact. But since you tested it should be fine 👍

[OskarStark]

Thanks!