[ruby/fiddle] support for very old libffi
Define Fiddle::TYPE_VARIADIC only when ffi_prep_cif_var is available, otherwise skip the test for it.
Fiddle::TYPE_VARIADIC
ffi_prep_cif_var
[ruby/fiddle] support for very old libffi
Define
Fiddle::TYPE_VARIADIConly whenffi_prep_cif_varisavailable, otherwise skip the test for it.