Add Support for sctp_status in getsockopt

gtests/net/packetdrill/tests/bsd/sctp/sctp_get_socket_options.pkt

+0 socket(..., SOCK_STREAM, IPPROTO_SCTP) = 3
++0.0 fcntl(3, F_GETFL) = 0x2 (flags O_RDWR)
++0.0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0
+// Check the handshake with an empty(!) cookie
++0.1 connect(3, ..., ...) = -1 EINPROGRESS (Operation now in progress)
++0.0 > sctp: INIT[flgs=0, tag=1, a_rwnd=..., os=..., is=..., tsn=1, ...]
++0.1 < sctp: INIT_ACK[flgs=0, tag=2, a_rwnd=1500, os=1, is=1, tsn=1, STATE_COOKIE[len=4, val=...]]
++0.0 > sctp: COOKIE_ECHO[flgs=0, len=4, val=...]
++0.1 < sctp: COOKIE_ACK[flgs=0]
+
++0.0 getsockopt(3, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
+
++0 setsockopt(3, IPPROTO_SCTP, SCTP_RTOINFO, {srto_initial=100, srto_max=200, srto_min=50}, 16) = 0
++0 getsockopt(3, IPPROTO_SCTP, SCTP_RTOINFO, {srto_initial=100, srto_max=200, srto_min=50}, [16]) = 0
+
++0 getsockopt(3, IPPROTO_SCTP, SCTP_STATUS, {sstat_state=8, sstat_rwnd=1500, sstat_unackdata=0, sstat_penddata=0, sstat_instrms=1, sstat_outstrms=1, 
+sstat_fragmentation_point=1452, 
+sstat_primary=...}, 
+[176])= 0
+
++0 setsockopt(3, SOL_SOCKET, SO_LINGER, {onoff=1, linger=30}, 8) = 0
++0 getsockopt(3, SOL_SOCKET, SO_LINGER, {onoff=128, linger=30}, [8]) = 0
+
+
++0 close(3) = 0
+