fix hdf5 1.12 build

[fulminemizzega]

Hello, I've managed to get this to work, it builds and passes all the tests (with many warnings):
101 passed, 506 warnings

INFO :: The inputs making up the hashes for the built packages are as follows:
{
  "pynio-1.5.5-py39hf69c57c_13": {
    "recipe": {
      "c_compiler": "gcc",
      "c_compiler_version": "9",
      "channel_targets": "conda-forge main",
      "cxx_compiler": "gxx",
      "cxx_compiler_version": "9",
      "fortran_compiler": "gfortran",
      "fortran_compiler_version": "9",
      "hdf4": "4.2.15",
      "hdf5": "1.12.1",
      "jasper": "2",
      "libgdal": "3.3",
      "libnetcdf": "4.8.1",
      "numpy": "1.19",
      "proj": "8.2.0",
      "python": "3.9.* *_cpython",
      "target_platform": "linux-64"
    }
  }
}