audio: Opening via a logical device ID should also track default device.

As these will change devices as the default device changes, in the future,
we would want the original and new logical device to stay together.

src/audio/SDL_audio.c

@@ -1160,10 +1160,21 @@ SDL_AudioDeviceID SDL_OpenAudioDevice(SDL_AudioDeviceID devid, const SDL_AudioSp
         is_default = SDL_TRUE;
     }
 
+    // this will let you use a logical device to make a new logical device on the parent physical device. Could be useful?
+    SDL_AudioDevice *device = NULL;
+    const SDL_bool islogical = (devid & (1<<1)) ? SDL_FALSE : SDL_TRUE;
+    if (!islogical) {
+        device = ObtainPhysicalAudioDevice(devid);
+    } else {
+        SDL_LogicalAudioDevice *logdev = ObtainLogicalAudioDevice(devid);  // this locks the physical device, too.
+        if (logdev) {
+            is_default = logdev->is_default;  // was the original logical device meant to be a default? Make this one, too.
+            device = logdev->physical_device;
+        }
+    }
+
     SDL_AudioDeviceID retval = 0;
 
-    // this will let you use a logical device to make a new logical device on the parent physical device. Could be useful?
-    SDL_AudioDevice *device = ObtainPhysicalAudioDevice(devid);
     if (device) {
         SDL_LogicalAudioDevice *logdev = (SDL_LogicalAudioDevice *) SDL_calloc(1, sizeof (SDL_LogicalAudioDevice));
         if (!logdev) {