reverting HDF5 change: it breaks our nightly builds

CMakeLists.txt

@@ -825,10 +825,8 @@ if(ENABLE_FOURIER_MODEL)
 endif(ENABLE_FOURIER_MODEL)
 
 if(ENABLE_MED OR ENABLE_CGNS)
-  find_package(HDF5)
-  if(HDF5_FOUND)
-    set(HDF5_LIB "${HDF5_C_LIBRARIES}")
-    list(APPEND EXTERNAL_INCLUDES ${HDF5_INCLUDE_DIRS})
+  find_library(HDF5_LIB hdf5)
+  if(HDF5_LIB)
     if(ENABLE_MED)
       find_library(MED_LIB med)
       if(MED_LIB)
@@ -859,9 +857,9 @@ if(ENABLE_MED OR ENABLE_CGNS)
         endif(ZLIB_FOUND)
       endif(NOT HAVE_LIBZ)
     endif(MED_LIB OR CGNS_LIB)
-  else(HDF5_FOUND)
+  else(HDF5_LIB)
     message(STATUS "HDF5 not found")
-  endif(HDF5_FOUND)
+  endif(HDF5_LIB)
 endif(ENABLE_MED OR ENABLE_CGNS)
 
 if(HAVE_SOLVER)