all: adjust defs for Dragonfly BSD

- DragonFly BSD removed RTM_OLDADD and RTM_OLDDEL
  constants on Aug 4th, 2017 and are now gone in both master
  branch and RELEASE 5.6. It also removed IPV6_IPSEC_POLICY
  constant since IPSEC was removed from base and kernel.

Change-Id: I99fbdfcb95fb276374f7b2dbd5fa30fe3f30f709
GitHub-Last-Rev: 1f27a0e26eb729e2004cb04018e34812d3395f4f
GitHub-Pull-Request: golang/net#54
Reviewed-on: https://go-review.googlesource.com/c/net/+/197599
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Run-TryBot: Benny Siegert <bsiegert@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ipv6/defs_dragonfly.go

@@ -30,8 +30,6 @@ const (
 	sysIPV6_CHECKSUM = C.IPV6_CHECKSUM
 	sysIPV6_V6ONLY   = C.IPV6_V6ONLY
 
-	sysIPV6_IPSEC_POLICY = C.IPV6_IPSEC_POLICY
-
 	sysIPV6_RTHDRDSTOPTS = C.IPV6_RTHDRDSTOPTS
 	sysIPV6_RECVPKTINFO  = C.IPV6_RECVPKTINFO
 	sysIPV6_RECVHOPLIMIT = C.IPV6_RECVHOPLIMIT

route/defs_dragonfly.go

@@ -61,8 +61,6 @@ const (
 	sysRTM_REDIRECT   = C.RTM_REDIRECT
 	sysRTM_MISS       = C.RTM_MISS
 	sysRTM_LOCK       = C.RTM_LOCK
-	sysRTM_OLDADD     = C.RTM_OLDADD
-	sysRTM_OLDDEL     = C.RTM_OLDDEL
 	sysRTM_RESOLVE    = C.RTM_RESOLVE
 	sysRTM_NEWADDR    = C.RTM_NEWADDR
 	sysRTM_DELADDR    = C.RTM_DELADDR