Auto merge of #1311 - cynecx:canonicalize_pointer_ty, r=emilio

 Canonicalize a type (pointer type) first before checking for constness

This fixes cases like:

```cpp
int sodium_munlock(int* const addr); // addr itself is const but the pointer points to mutable data
```

Before fix:

```rust
extern "C" {
    pub fn sodium_munlock(
        addr: *const ::std::os::raw::c_int,
    ) -> ::std::os::raw::c_int;
}

```

After this patch:
```rust
extern "C" {
    pub fn sodium_munlock(
        addr: *mut ::std::os::raw::c_int,
    ) -> ::std::os::raw::c_int;
}
```

0 files changed, 0 insertions, 0 deletions