Add --require-audio

By default, scrcpy mirrors only the video when audio capture fails on
the device. Add an option to force scrcpy to fail if audio is enabled
but does not work.

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

app/src/options.c

@@ -72,6 +72,7 @@ const struct scrcpy_options scrcpy_options_default = {
     .start_fps_counter = false,
     .power_on = true,
     .audio = true,
+    .require_audio = false,
     .list_encoders = false,
     .list_displays = false,
 };