Fix race condition on OpenALAudioOut (#448)

Ryujinx.Audio/OpenAL/OpenALAudioOut.cs

@@ -181,9 +181,12 @@ namespace Ryujinx.Audio.OpenAL
             do
             {
                 foreach (Track Td in Tracks.Values)
+                {
+                    lock (Td)
                     {
                         Td.CallReleaseCallbackIfNeeded();
                     }
+                }
 
                 //If it's not slept it will waste cycles.
                 Thread.Sleep(10);