SCTP: Make sctp_verify_param return multiple indications.

SCTP: Make sctp_verify_param return multiple indications.

SCTP-AUTH and future ADD-IP updates have a requirement to
do additional verification of parameters and an ability to
ABORT the association if verification fails.  So, introduce
additional return code so that we can clear signal a required
action.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>