OPTION_MPTCP_MPC_SYN
if (OPTION_MPTCP_MPC_SYN & opts->suboptions) {
opts->suboptions = OPTION_MPTCP_MPC_SYN;
subopt = OPTION_MPTCP_MPC_SYN;
#define OPTIONS_MPTCP_MPC (OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_SYNACK | \
opt_mp_capable = !!(mp_opt.suboptions & OPTION_MPTCP_MPC_SYN);
(OPTION_MPTCP_MPC_SYN | OPTION_MPTCP_MPC_ACK)))