`windows-bindgen` _Impl trait should use `unsafe fn` if any of its parameters are pointers

Nobody has claimed this yet.

### Which crate is this about?

windows

### Crate version

0.32.0

### Summary

```rust
#[implement(Windows::Win32::Graphics::Imaging::IWICBitmapFrameDecode)]
pub struct Foo {}

impl IWICBitmapSource_Impl for Foo {
fn GetSize(&mut self, puiwidth: *mut u32, puiheight: *mut u32) -> windows::core::Result<()> {
unsafe {
*puiwidth = 0u32;
*puiheight = 0u32;
}
Ok(())
}
/* ... */
}
```

### Expected behavior

It should be an `unsafe fn` as the implementation is expected to dereference the pointer parameters.

### Actual behavior

Everything is just a safe `fn`.

### Additional comments

`cargo clippy` is unsatisfied:

```
error: this public function might dereference a raw pointer but is not marked `unsafe`
--> src\lib.rs:149:14
|
149 | *puiwidth = self.decoded.borrow().basic_info.xsize;
| ^^^^^^^^
|
= note: `#[deny(clippy::not_unsafe_ptr_arg_deref)]` on by default
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#not_unsafe_ptr_arg_deref
```

Start in the windows-bindgen code that generates _Impl trait method signatures, using the GetSize example as the target case. Check how pointer parameters are represented, then run cargo clippy on an implementation that dereferences them; done means the generated method is unsafe and the not_unsafe_ptr_arg_deref warning is resolved.

Written by the indexing model from the issue text.