Convert sunaudio.py to bytes. (It has no unit test of its own!)

Fix test_ossaudiodev by closing the dsp properly (it can't be opened
multiple times on my box).

Lib/test/test_ossaudiodev.py

@@ -170,6 +170,7 @@ def test_main():
                            errno.ENODEV, errno.EBUSY):
             raise TestSkipped(msg)
         raise
+    dsp.close()
     test_support.run_unittest(__name__)
 
 if __name__ == "__main__":