add symbol SCTP_GET_ASSOC_NUMBER for socketoption

gtests/net/packetdrill/symbols_freebsd.c

@@ -107,6 +107,7 @@ struct int_symbol platform_symbols_table[] = {
 	{ SCTP_DEFAULT_PRINFO,              "SCTP_DEFAULT_PRINFO"             },
 	{ SCTP_STATUS,                      "SCTP_STATUS"                     },
 	{ SCTP_GET_PEER_ADDR_INFO,          "SCTP_GET_PEER_ADDR_INFO"         },
+	{ SCTP_GET_ASSOC_NUMBER,            "SCTP_GET_ASSOC_NUMBER"           },
 	{ SCTP_FRAGMENT_INTERLEAVE,         "SCTP_FRAGMENT_INTERLEAVE"        },
 #if defined(SCTP_INTERLEAVING_SUPPORTED)
 	{ SCTP_INTERLEAVING_SUPPORTED,      "SCTP_INTERLEAVING_SUPPORTED"     },

gtests/net/packetdrill/tests/bsd/sctp/api_tests/getsockopt/sctp_get_assoc_number.pkt

@@ -10,6 +10,6 @@
 
 +0 getsockopt(3, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
 
-+0 getsockopt(3, IPPROTO_SCTP, SCTP_GET_ASSOC_NUMBER, [0], [4]) = -1
++0 getsockopt(3, IPPROTO_SCTP, SCTP_GET_ASSOC_NUMBER, [1], [4]) = -1
 
 +0 close(3) = 0