hdf5_ep

Merge pull request #1720 in HDFFV/hdf5 from ~LRKNOX/hdf5_lrk:develop to develop

* commit '931abe94244c94e106835250e2f723f634a61c8c':
  Move set (MAX_PROC_COUNT 8) back to HPC options files.
  Move check for MPI defined to enable parallel from options scripts in HPC to config/cmake/HDF5options.cmake.