hdf5_ep

[svn-r6426] Purpose:
    Update
Description:
    Final support addition for FPHDF5. Wherever there was an equivalent
    MPIO or MPIO/POSIX call/check, I placed an FPHDF5 call/check there as
    well, with the appropriate #ifdefs in place.

    The hdf5.h is updated with the H5FDfphdf5.h driver #include.
Platforms tested:
    Linux & Modi4