chore: satisfy clippy

src/ppu.rs

@@ -797,21 +797,12 @@ impl Default for BackgroundFetcher {
     }
 }
 
-#[derive(Debug)]
+#[derive(Debug, Default)]
 struct ObjectFetcher {
     state: FetcherState,
     tile: TileBuilder,
 }
 
-impl Default for ObjectFetcher {
-    fn default() -> Self {
-        Self {
-            state: Default::default(),
-            tile: Default::default(),
-        }
-    }
-}
-
 impl Fetcher for ObjectFetcher {
     fn reset(&mut self) {
         self.state = Default::default();