paaudio: fix playback glitches

Pulseaudio normally assumes that when the server wants it, the client
can generate the audio samples and send it right away.  Unfortunately
this is not the case with QEMU -- it's up to the emulated system when
does it generate the samples.  Buffering the samples and sending them
from a background thread is just a workaround, that doesn't work too
well.  Instead enable pa's compatibility support and let pa worry about
the details.

Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Message-id: aa4e3613122ccbaa62b1feb4e427260731f7477c.1566168923.git.DirtY.iCE.hu@gmail.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

audio/paaudio.c

@@ -512,10 +512,8 @@ static pa_stream *qpa_simple_new (
 
     flags =
         PA_STREAM_INTERPOLATE_TIMING
-#ifdef PA_STREAM_ADJUST_LATENCY
-        | PA_STREAM_ADJUST_LATENCY
-#endif
-        | PA_STREAM_AUTO_TIMING_UPDATE;
+        | PA_STREAM_AUTO_TIMING_UPDATE
+        | PA_STREAM_EARLY_REQUESTS;
 
     if (dev) {
         /* don't move the stream if the user specified a sink/source */