target/xtensa: Finalize config in xtensa_register_core()

Make XtensaConfigList::config not const. Only modify
XtensaConfig within xtensa_register_core(), when the
class is registered, not when it is initialized.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Message-Id: <20250210133134.90879-4-philmd@linaro.org>
2 files changed