rust: enable `raw_ref_op` feature

Since Rust 1.82.0 the `raw_ref_op` feature is stable [1].

By enabling this feature we can use `&raw const place` and
`&raw mut place` instead of using `addr_of!(place)` and
`addr_of_mut!(place)` macros.

Allowing us to reduce macro complexity, and improve consistency
with existing reference syntax as `&raw const`, `&raw mut` are
similar to `&`, `&mut` making it fit more naturally with other
existing code.

Suggested-by: Benno Lossin <benno.lossin@proton.me>
Link: https://github.com/Rust-for-Linux/linux/issues/1148
Link: https://blog.rust-lang.org/2024/10/17/Rust-1.82.0.html#native-syntax-for-creating-a-raw-pointer

 [1]
Signed-off-by: Antonio Hickey <contact@antoniohickey.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/20250320020740.1631171-2-contact@antoniohickey.com


[ Removed dashed line change as discussed. Added Link to the explanation
  of the feature in the Rust 1.82.0 release blog post. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>