Hi, when I build this: https://github.com/antoinevg/nucleo-h7xx

I get these errors:

```
error[E0793]: reference to packed field is unaligned
   --> /home/sven/.cargo/registry/src/index.crates.io-6f17d22bba15001f/stm32h7xx-hal-0.9.0/src/ethernet/eth.rs:306:32
    |
306 |         let address = unsafe { self.rbuf[x].as_ptr() as u32 };
    |                                ^^^^^^^^^^^^^^^^^^^^^
    |
    = note: packed structs are only aligned by one byte, and many modern architectures penalize unaligned field accesses
    = note: creating a misaligned reference is undefined behavior (even if that reference is never dereferenced)
    = help: copy the field contents to a local variable, or replace the reference with a raw pointer and use `read_unaligned`/`write_unaligned` (loads and stores via `*p` must be properly aligned even when using raw pointers)
```

How can this be fixed?