Allow up to 48 buffers in AL raw samples queue.

Assuming Vorbis frame of 128 samples at 48 kHz sampling rate, 48 buffers
will let the client run at 7.8 FPS without underruns. Current value of
16 only allows 23.4 FPS minimum, which is not enough for continuous
playback in minimized state (at 10 FPS).

Fixes #326.

src/client/sound/al.c

@@ -393,12 +393,17 @@ static void AL_StreamStop(void)
     Q_assert(!s_stream_buffers);
 }
 
+static bool AL_NeedRawSamples(void)
+{
+    return s_stream_buffers < 48;
+}
+
 static bool AL_RawSamples(int samples, int rate, int width, int channels, const byte *data, float volume)
 {
     ALenum format = AL_FORMAT_MONO8 + (channels - 1) * 2 + (width - 1);
     ALuint buffer = 0;
 
-    if (s_stream_buffers < 16) {
+    if (AL_NeedRawSamples()) {
         qalGetError();
         qalGenBuffers(1, &buffer);
         if (qalGetError())
@@ -427,11 +432,6 @@ static bool AL_RawSamples(int samples, int rate, int width, int channels, const
     return true;
 }
 
-static bool AL_NeedRawSamples(void)
-{
-    return s_stream_buffers < 16;
-}
-
 static void AL_UpdateUnderWater(void)
 {
     bool underwater = S_IsUnderWater();