Function krb5_sys::krb5_c_make_checksum_iov

pub unsafe extern fn krb5_c_make_checksum_iov(context: krb5_context,
                                              cksumtype: krb5_cksumtype,
                                              key: *const krb5_keyblock,
                                              usage: krb5_keyusage,
                                              data: *mut krb5_crypto_iov,
                                              num_data: usize)
                                              -> krb5_error_code