Revert away from automatically generating port_ipv6.h, and install

a static once-generated version instead.  We know we have IPv6
headers available here.

The probing was problematical for several reasons:
 o it probed the host headers, not the headers in the build or DESTDIR
   tree (could be fixed in another way)
 o the probe_ipv6 script mucks with PATH, which would be problematical
   for cross compilation.

dist/bind/include/port_ipv6.h

@@ -0,0 +1,9 @@
+
+/* This file is automatically generated. Do Not Edit. */
+
+#ifndef port_ipv6_h
+#define port_ipv6_h
+
+#define HAS_INET6_STRUCTS
+
+#endif

usr.sbin/bind/lib/Makefile

@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.8 2000/03/01 10:50:02 itojun Exp $
+#	$NetBSD: Makefile,v 1.9 2000/05/06 16:07:43 he Exp $
 
 LIB=bind
 
@@ -55,15 +55,4 @@ SRCS+=	dns.c dns_gr.c dns_ho.c dns_nw.c dns_pr.c dns_pw.c \
 # only needed during build
 libinstall::
 
-port_ipv6.h:
-	env CC="${CC}" CPPFLAGS="${CPPFLAGS}" /bin/sh \
-	${BIND_DIST_DIR}/bin/probe_ipv6
-
-CLEANFILES+=port_ipv6.h
-
-# mention explicit dependency, so port_ipv6.h will appear timely
-res_debug.c: port_ipv6.h
-
 .include <bsd.lib.mk>
-
-${OBJS}: port_ipv6.h