message: Add missing documentation for GnuHash object
diff: @@ -121,6 +121,17 @@ Symbol Version Auxiliary
  ----------
  +GNU Hash table
  +**************
  +
  +.. autoclass:: lief.ELF.GnuHash
  + :members:
  + :inherited-members:
  + :undoc-members:
  +
  +----------
  +
  +
  Builder
  *******
  