Function hgdirectffi::rustlazyancestors_init

#[no_mangle]
pub extern "C" fn rustlazyancestors_init(
    index: *mut c_void, 
    initrevslen: ssize_t, 
    initrevs: *mut c_long, 
    stoprev: c_long, 
    inclusive: c_int
) -> *mut AncestorsIterator<Index>

Wrapping of AncestorsIterator constructor, for C callers.

Besides initrevs, stoprev and inclusive, that are converted we receive the index and the parents function as pointers