rust: kernel: remove #[allow(clippy::new_ret_no_self)]

Clippy triggered a false positive on its `new_ret_no_self` lint
when using the `pin_init!` macro. Since Rust 1.67.0, that does
not happen anymore, since Clippy learnt to not warn about
`-> impl Trait<Self>` [1][2].

The kernel nowadays uses Rust 1.72.1, thus remove the `#[allow]`.

Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Finn Behrens <me@kloenk.dev>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Link: https://github.com/rust-lang/rust-clippy/issues/7344 [1]
Link: https://github.com/rust-lang/rust-clippy/pull/9733 [2]
Link: https://lore.kernel.org/r/20230923024707.47610-1-gary@garyguo.net
[ Reworded slightly and added a couple `Link`s. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

rust/kernel/sync/condvar.rs

@@ -91,7 +91,6 @@ unsafe impl Sync for CondVar {}
 
 impl CondVar {
     /// Constructs a new condvar initialiser.
-    #[allow(clippy::new_ret_no_self)]
     pub fn new(name: &'static CStr, key: &'static LockClassKey) -> impl PinInit<Self> {
         pin_init!(Self {
             _pin: PhantomPinned,

rust/kernel/sync/lock.rs

@@ -99,7 +99,6 @@ unsafe impl<T: ?Sized + Send, B: Backend> Sync for Lock<T, B> {}
 
 impl<T, B: Backend> Lock<T, B> {
     /// Constructs a new lock initialiser.
-    #[allow(clippy::new_ret_no_self)]
     pub fn new(t: T, name: &'static CStr, key: &'static LockClassKey) -> impl PinInit<Self> {
         pin_init!(Self {
             data: UnsafeCell::new(t),