message: fix  unsafe block
diff: @@ -546,14 +546,12 @@ impl<'a> RasterBand<'a> {
  0x00
  };
  - unsafe {
  let rv = unsafe { gdal_sys::GDALCreateMaskBand(self.c_rasterband, flags) };
  if rv != 0 {
  return Err(_last_cpl_err(rv));
  - }
  + };
  Ok(())
  }
  - }
  /// Open the mask-`Rasterband`
  pub fn open_mask_band(&self) -> Result<RasterBand> {
  