Add --audio-buffer

Expose an option to add a buffering delay (in milliseconds) before
playing audio.

This is similar to the options --display-buffer and --v4l2-buffer for
video frames.

PR #3757 <https://github.com/Genymobile/scrcpy/pull/3757>

app/src/scrcpy.c

@@ -687,7 +687,7 @@ aoa_hid_end:
         sc_frame_source_add_sink(src, &s->screen.frame_sink);
 
         if (options->audio) {
-            sc_audio_player_init(&s->audio_player, SC_TICK_FROM_MS(50));
+            sc_audio_player_init(&s->audio_player, options->audio_buffer);
             sc_frame_source_add_sink(&s->audio_decoder.frame_source,
                                      &s->audio_player.frame_sink);
         }