nil: cleanup derelict allow(dead_code) annotations

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/38807>

src/nouveau/nil/extent.rs

@@ -219,7 +219,6 @@ impl<U> Offset4D<U> {
         }
     }
 
-    #[allow(dead_code)]
     pub fn is_aligned_to(&self, alignment: Extent4D<U>) -> bool {
         (self.x % alignment.width) == 0
             && (self.y % alignment.height) == 0

src/nouveau/nil/image.rs

@@ -991,7 +991,6 @@ pub enum ViewType {
 }
 
 /// An enum describing how an image view will be accessed by the shader.
-#[allow(dead_code)]
 #[derive(Clone, Debug, Copy, PartialEq)]
 #[repr(u8)]
 pub enum ViewAccess {

src/nouveau/nil/modifiers.rs

@@ -118,7 +118,6 @@ impl GOBType {
 }
 
 #[repr(u8)]
-#[allow(dead_code)]
 #[derive(Clone, Copy, Eq, PartialEq)]
 pub enum CompressionType {
     None = 0,