[Feature Request]: Add kernels selectable in armbian-config to armbian/build

### Which feature would you like to have?

Would it be possible to add selection of the older prebuilt kernels, kernel headers etc in `armbian-config` https://github.com/armbian/configng to be selectable in the EXPERT mode of build.

I tried looking at the `armbian-config` code and it looks quite complex with a sub module being loaded for the kernel functionality, otherwise would have done a pull request by now.

This would go a long way to addressing the problems with maintaining older versions of Armbian that are no longer buildable.

### Funding

- [ ] [I am willing to cover expenses](https://www.armbian.com/contact/)