[host] nvfbc: always update cursor shape on startup

This ensures that the top-left position of the cursor sprite is correctly
computed.

host/platform/Windows/capture/NVFBC/src/nvfbc.c

@@ -351,6 +351,8 @@ static CaptureResult nvfbc_getFrame(FrameBuffer * frame)
 
 static int pointerThread(void * unused)
 {
+  lgSignalEvent(this->cursorEvents[1]);
+
   while(!this->stop)
   {
     LGEvent * events[2];