WASAPI_WaitDevice: Check current padding before waiting on event

During playback, don't queue another buffer unless there are none in the queue.

During capture, there may be multiple buffers of audio available.
WASAPI_CaptureFromDevice only processes one buffer, and if we always wait on the next event, we will never catch up if it falls behind.

src/audio/wasapi/SDL_wasapi.c

@@ -463,20 +463,22 @@ static int WASAPI_WaitDevice(SDL_AudioDevice *device)
 {
     // WaitDevice does not hold the device lock, so check for recovery/disconnect details here.
     while (RecoverWasapiIfLost(device) && device->hidden->client && device->hidden->event) {
-        DWORD waitResult = WaitForSingleObjectEx(device->hidden->event, 200, FALSE);
-        if (waitResult == WAIT_OBJECT_0) {
+        UINT32 padding = 0;
+        if (!WasapiFailed(device, IAudioClient_GetCurrentPadding(device->hidden->client, &padding))) {
             const UINT32 maxpadding = device->sample_frames;
-            UINT32 padding = 0;
-            if (!WasapiFailed(device, IAudioClient_GetCurrentPadding(device->hidden->client, &padding))) {
-                //SDL_Log("WASAPI EVENT! padding=%u maxpadding=%u", (unsigned int)padding, (unsigned int)maxpadding);*/
-                if (device->iscapture && (padding > 0)) {
-                    break;
-                } else if (!device->iscapture && (padding <= maxpadding)) {
-                    break;
-                }
+            //SDL_Log("WASAPI %s EVENT! padding=%u maxpadding=%u", device->iscapture ? "CAPTURE" : "PLAYBACK", (unsigned int)padding, (unsigned int)maxpadding);
+            if (device->iscapture ? (padding > 0) : (padding < maxpadding)) {
+                break;
             }
-        } else if (waitResult != WAIT_TIMEOUT) {
-            //SDL_Log("WASAPI FAILED EVENT!");*/
+        }
+
+        switch (WaitForSingleObjectEx(device->hidden->event, 200, FALSE)) {
+        case WAIT_OBJECT_0:
+        case WAIT_TIMEOUT:
+            break;
+
+        default:
+            //SDL_Log("WASAPI FAILED EVENT!");
             IAudioClient_Stop(device->hidden->client);
             return -1;
         }