Do USE_(DT_)CODE_PARTITION and FLASH_LOAD_OFFSET/SIZE need to be user-configurable?

[ulfalizer]

See discussion near the end of #20673. It might be possible to improve #20740 some more if they weren't (though it already improves the situation, so no need to block it I think).

Recording it mostly so I don't forget it, and in case someone jumps in.

CC @novalisek

[ulfalizer]

Having USE_DT_CODE_PARTITION (was called USE_CODE_PARTITION before the linked PR) user-configurable seems the sketchiest out of them.

[github-actions]

This issue has been marked as stale because it has been open (more than) 60 days with no activity. Remove the stale label or add a comment saying that you would like to have the label removed otherwise this issue will automatically be closed in 14 days. Note, that you can always re-open a closed issue at any time.