feat(snd): implement audio playback using rodio

src/cpu.rs

@@ -3,6 +3,7 @@ use crate::instruction::{Cycle, Instruction};
 use crate::interrupt::{InterruptEnable, InterruptFlag};
 use crate::joypad::Joypad;
 use crate::ppu::Ppu;
+use crate::sound::SampleSender;
 use crate::timer::Timer;
 use bitfield::bitfield;
 use std::fmt::{Display, Formatter, Result as FmtResult};
@@ -44,6 +45,10 @@ impl Cpu {
         })
     }
 
+    pub fn set_audio_src(&mut self, sender: SampleSender) {
+        self.bus.pass_audio_src(sender)
+    }
+
     pub(crate) fn ime(&self) -> ImeState {
         self.ime
     }