Defines starting with `s' in netccitt

• SABM netccitt/hdlc.h:132
• SABM_CONTROL netccitt/hdlc.h:105
• SABM_SENT netccitt/hdlc.h:121
• SENT_CALL netccitt/pk.h:160
• SENT_CLEAR netccitt/pk.h:163
• SIOCGIFCONF_X25 netccitt/x25.h:155
• SIOCSIFCONF_X25 netccitt/x25.h:154