STM32H5 GPIOs

~~I noticed that the PEx and PFx pins are missing from `Peripherals` struct.~~ - Missread the nucleo doc

~~Also~~

```
let mut pin = Output::new(p.PC15, ...);
pin.toggle();
```

does not output anything. I believe that pin is used for OSC32, I imagine there is something extra that needs to be done? Should that be handled by embassy or by the user?