My shenanigans in `softdevice` experimentation continues! I've come across an interesting issue I hope there might be ideas for how to solve here :)

Lets say the `softdevice` wants to create an object on the user side so there can be state for some operation. I'm not able to figure out how to create this opaque structure so one can on the `softdevice` side have an FFI `new() -> MyOpaqueState` that later can be used on the user-side.
I guess one can have an API to tell the size of the struct the `softdevice` wants to create and give it as a correctly aligned and allocated pointer to the `softdevice` for initialization - but I'd hope this to be the last solution. Preferably I'd like to construct this object directly in the user-side stack.

Is this possible somehow?