Defines starting with `a' in bsd/netccitt

• A bsd/netccitt/hdlc.h:173
• ABM bsd/netccitt/hdlc.h:142
• ADDRESS_A bsd/netccitt/hdlc.h:89
• ADDRESS_B bsd/netccitt/hdlc.h:90
• ADDRLN bsd/netccitt/pk.h:109