hdf5 2021-09-07 (4806ed03)

Code extracted from:

    https://gitlab.kitware.com/third-party/hdf5.git

at commit 4806ed03eed8c2ee77bc0ea9fd22306d6e88bd03 (for/vtk-20210907-1.12.1).

CMakeLists.txt

@@ -555,10 +555,12 @@ endif ()
 
 #-----------------------------------------------------------------------------
 # perl is used in some optional src and tests, check availability
+if (FALSE) # VTK doesn't expose where this is used anyways.
 find_package (Perl)
 if (PERL_FOUND)
   set (H5_PERL_FOUND YES)
 endif ()
+endif ()
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------