Allow restarts and [sctp-dm-o-4-2-1.pkt](https://github.com/nplab/ETSI-SCTP-Conformance-Testsuite/blob/master/sctp-dm-tests/sctp-dm-o-4-2-1.pkt) to be handled correctly.
Allow restarts and sctp-dm-o-4-2-1.pkt to be handled correctly.