chore: remove various warnings

src/apu.rs

@@ -168,14 +168,6 @@ impl Apu {
         self.prod = Some(prod);
     }
 
-    #[inline]
-    pub(crate) fn is_full(&self) -> bool {
-        match self.prod.as_ref() {
-            Some(prod) => prod.is_full(),
-            None => false,
-        }
-    }
-
     /// 0xFF26 | NR52 - Sound On/Off
     pub(crate) fn set_status(&mut self, byte: u8) {
         self.ctrl.enabled = (byte >> 7) & 0x01 == 0x01;

src/apu/gen.rs

@@ -43,11 +43,6 @@ impl<T> SampleProducer<T> {
         self.inner.push(value)
     }
 
-    #[inline]
-    pub(crate) fn is_full(&self) -> bool {
-        self.inner.is_full()
-    }
-
     #[inline]
     pub(crate) fn two_available(&self) -> bool {
         self.inner.slots() > 2

src/bus.rs

@@ -66,10 +66,6 @@ impl Bus {
         self.cartridge.as_ref()?.title()
     }
 
-    pub(crate) fn apu(&self) -> &Apu {
-        &self.apu
-    }
-
     pub(crate) fn clock(&mut self) {
         self.ppu.clock();
         self.timer.clock();