Remove HDF5 Build Hacks

[henryleberre]

The situation has improved significantly since this was filed. HDF5 is no longer always built (we now call find_package(HDF5) first). The custom FindHDF5.cmake was split into a Cray-specific copy at toolchain/cmake/cce/FindHDF5.cmake. The patch is now just 2 lines — changing set(CMAKE_MODULE_PATH ...) to list(APPEND CMAKE_MODULE_PATH ...) in Silo's CMakeLists.txt.

An upstream PR to LLNL/Silo to fix this properly has been opened: llnl/Silo#550

Closing in favor of a new tracking issue for the MFC-side cleanup once that PR is merged.

[sbryngelson]

Thanks for documenting this well, @henryleberre

[Malmahrouqi3]

Gotta overtake this. ig robust SiloFindHDF5.cmake ought to be in place. Silo seems to be actively maintained still, so if figured out, I will PR changes to LLNL/Silo repo.

Error w/o Injecting FindHDF5.cmake

CMake Error at CMake/SiloFindHDF5.cmake:92 (message):
  An explicit request for HDF5 was made but HDF5 was not found.  You may want
  to try setting SILO_HDF5_DIR
Call Stack (most recent call first):
  CMakeLists.txt:202 (include)