Correct minor errors in efikeygen.

Signed-off-by: Peter Jones <pjones@redhat.com>
[pesign-client] Fix a wrong error message in handle_signing()

Vivek noticed that I copy-pastad an error block from
handle_unlock_token() into handle_signing() and forgot to chane it.

Signed-off-by: Peter Jones <pjones@redhat.com>