hdf5_ep

Merge pull request #1941 in HDFFV/hdf5 from ~BYRN/hdf5_adb:hdf5_1_8 to hdf5_1_8

* commit '37d7b75b95ce7c520a2254039c5179002443136f':
  Add missing comma
  Add new toolchain file
  Fix for statement declare variable
  Add clang toolchain
  HDFFV-10905 check for zlib available
  Fix missing option and incorrect close
  HDFFV-10903 merge S3 from dev