added Berkeley specific header

added Berkeley specific header

SCCS-vsn: lib/libc/net/getnetbyaddr.c 5.5
SCCS-vsn: lib/libc/net/getnetbyname.c 5.4
SCCS-vsn: lib/libc/net/getnetent.c 5.4
SCCS-vsn: lib/libc/net/getproto.c 5.4
SCCS-vsn: lib/libc/net/getprotoent.c 5.4
SCCS-vsn: lib/libc/net/getprotoname.c 5.4
SCCS-vsn: lib/libc/net/getservbyname.c 5.4
SCCS-vsn: lib/libc/net/getservbyport.c 5.4
SCCS-vsn: lib/libc/net/getservent.c 5.5
SCCS-vsn: lib/libc/net/herror.c 6.2
SCCS-vsn: lib/libc/net/rcmd.c 5.16
SCCS-vsn: lib/libc/net/res_comp.c 6.12
SCCS-vsn: lib/libc/net/res_debug.c 5.22
SCCS-vsn: lib/libc/net/res_init.c 6.8
SCCS-vsn: lib/libc/net/res_mkquery.c 6.7
SCCS-vsn: lib/libc/net/res_send.c 6.19
SCCS-vsn: lib/libcompat/4.3/rexec.c 5.4
SCCS-vsn: lib/libcompat/4.3/ruserpass.c 5.4