Defines starting with `e' in bsd/netinet

• ea_byte bsd/netinet/if_ether.h:66
• ENCAP_PROTO bsd/netinet/ip_mroute.c:252
• ENCAP_TTL bsd/netinet/ip_mroute.c:251
• EXPIRE_TIMEOUT bsd/netinet/ip_mroute.c:230