Remove HDF5 Build Hacks

[henryleberre]

While CMake ships its own FindHDF5, we had to create our own toolchain/cmake/FindHDF5.cmake to accommodate non-cooperative systems and compilers (afaik only Cray CCE). This issue arises again when we attempt to build the LLNL Silo dependency because it uses the built-in (CMake-provided) FindHDF5. To work around this, we patch
Silo to allow us to inject our toolchain/cmake/FindHDF5.cmake. This is terrible. See:

MFC/toolchain/dependencies/Silo.patch

Lines 10 to 19 in 63c79cb

	diff --git a/CMakeLists.txt b/CMakeLists.txt
	index 111eb42..9e460f7 100644
	--- a/CMakeLists.txt
	+++ b/CMakeLists.txt
	@@ -68,7 +68,7 @@ project(Silo VERSION ${SILO_VERSION} LANGUAGES CXX C)
	###-----------------------------------------------------------------------------
	# location for Silo CMake includes
	###-----------------------------------------------------------------------------
	-set(CMAKE_MODULE_PATH ${Silo_SOURCE_DIR}/CMake)
	+list(APPEND CMAKE_MODULE_PATH "${Silo_SOURCE_DIR}/CMake")

MFC/toolchain/dependencies/CMakeLists.txt

Line 80 in 63c79cb

"$<$<STREQUAL:${CMAKE_Fortran_COMPILER_ID},Cray>:-DCMAKE_MODULE_PATH=${CMAKE_SOURCE_DIR}/../cmake>"

As a result of this, HDF5 is the last of our dependencies that we always build even when a compatible version is present on the system. This is also why the --sys-hdf5 command-line argument is still supported by ./mfc.sh but --sys-fftw and --sys-silo are no longer accepted.

Good luck to whoever is tasked with resolving this in the future. I do not think this will ever be fixed but I would like to be proven wrong.

[sbryngelson]

Thanks for documenting this well, @henryleberre