This breaks the API of GameBoyAdvanvce::save_state and restore_state methods.
Currently as WIP only SDL2 frontend will adjust.
Former-commit-id: 1df15c8697fef0f6adddb07a6d653947c622ba12
Former-commit-id: 2ea339dc6a0d1e7539d167c4df29694b408303da
While saving code re-use, it won't allow flexibility for special casing
specific size bus accesses which are much needed in order to emulate
open-bus and bios reads
Former-commit-id: 952a30a130612d61b3f5047b1f1c3cbda9bd58a8
Former-commit-id: ad3a25c012853399591d79f4f1a4423ea9e6645e