libffi_3_3: disable fortify3 hardening flag

pkgs/development/libraries/libffi/3.3.nix

···
     "--disable-exec-static-tramp"
   ];
 
+  # with fortify3, tests fail for some reason
+  hardeningDisable = [ "fortify3" ];
+
   preCheck = ''
     # The tests use -O0 which is not compatible with -D_FORTIFY_SOURCE.
     NIX_HARDENING_ENABLE=''${NIX_HARDENING_ENABLE/fortify/}