message: samples: fix callback function type
diff: @@ -14,7 +14,7 @@ Ptr<CLAHE> pFilter;
  int tilesize;
  int cliplimit;
  -static void TSize_Callback(int pos)
  +static void TSize_Callback(int pos, void* /*data*/)
  {
  if(pos==0)
  pFilter->setTilesGridSize(Size(1,1));
  @@ -22,7 +22,7 @@ static void TSize_Callback(int pos)
  pFilter->setTilesGridSize(Size(tilesize,tilesize));
  }
  -static void Clip_Callback(int)
  +static void Clip_Callback(int, void* /*data*/)
  {
  pFilter->setClipLimit(cliplimit);
  }
  