[krbdev.mit.edu #1224] asn1_k_encode.c: add_optstring always adds

[kenh@cmf.nrl.navy.mil via RT]

>The only code affected by this change is the sam challenge encoders.
>
>
>In draft-ietf-krb-wg-kerberos-sam-01.txt all of the fields are listed as
>optional general strings - so a zero length string should not be sent.

I guess it's a good thing I did the new sam checksum stuff the "right"
way, or this would have busted the checksum calculation for sure :-)

--Ken