TODO add more tests for all the instructions I've got implemented so
far.
Also, I need to rewrite the whole "sysbus" module again because it's
crap and I keep refactoring it as I go.
I've added the "Dummy" because the bios for some reason tries to memzero
an unmapped region on the work ram (the thumb loop that ends at 0x126)
Former-commit-id: 67befd0935ee10df9ac8ceeaebd14f69767a7f16