wineoss.drv: Cap reported OSS fill level to expected level.

Some devices apparently return that the buffer contains an extra frame
that we never wrote. We should account for that to avoid an integer
underflow.

dlls/wineoss.drv/mmdevdrv.c

@@ -1412,6 +1412,12 @@ static void oss_write_data(ACImpl *This)
     }else
         in_oss_frames = (This->oss_bufsize_bytes - bi.bytes) / This->fmt->nBlockAlign;
 
+    if(in_oss_frames > This->in_oss_frames){
+        TRACE("Capping reported frames from %u to %u\n",
+                in_oss_frames, This->in_oss_frames);
+        in_oss_frames = This->in_oss_frames;
+    }
+
     write_limit = 0;
     while(write_limit + in_oss_frames < max_period * 3)
         write_limit += max_period;