compile on freebsd 11

$go version
go version go1.8 freebsd/amd64

$cd /tmp
$git clone git://github.com/docker/docker.git
$cd docker
$./hack/make.sh
...
Building: bundles/17.04.0-dev/binary-daemon/dockerd-17.04.0-dev
.gopath/src/github.com/docker/docker/vendor/github.com/docker/libnetwork/drivers/bridge/bridge.go:22:2: no buildable Go source files in /tmp/docker/.gopath/src/github.com/docker/docker/vendor/github.com/docker/libnetwork/ns

$cp /tmp/docker/vendor/github.com/docker/libnetwork/ns/init_linux.go /tmp/docker/vendor/github.com/docker/libnetwork/ns/init_freebsd.go

$./hack/make.sh
...
.gopath/src/github.com/docker/docker/vendor/github.com/docker/libnetwork/ns/init_freebsd.go:67: undefined: syscall.Gettid
.gopath/src/github.com/docker/docker/vendor/github.com/docker/libnetwork/ns/init_freebsd.go:77: undefined: syscall.NETLINK_ROUTE
.gopath/src/github.com/docker/docker/vendor/github.com/docker/libnetwork/ns/init_freebsd.go:84: undefined: syscall.NETLINK_XFRM
.gopath/src/github.com/docker/docker/vendor/github.com/docker/libnetwork/ns/init_freebsd.go:99: undefined: syscall.AF_NETLINK
.gopath/src/github.com/docker/docker/vendor/github.com/docker/libnetwork/ns/init_freebsd.go:99: undefined: syscall.NETLINK_XFRM

Does syscall.Gettid, syscall.NETLINK_ROUTE, syscall.NETLINK_XFRM, syscall.AF_NETLINK, syscall.NETLINK_XFRM not exist for Freebsd?
So, I did move it all from init_freebsd.go for testing only!

$cat /tmp/docker/vendor/github.com/docker/libnetwork/ns/init_freebsd.go
package ns

import (

)

$./hack/make.sh

$ls -l /tmp/docker/bundles/17.04.0-dev/binary-client/docker-17.04.0-dev
-rwxr-xr-x 1 root wheel 12386457 8 марта 16:22 /tmp/docker/bundles/17.04.0-dev/binary-client/docker-17.04.0-dev

So, libnetwork doesn't compile for me on freebsd 11 without any ns/init_freebsd.go
So, should add ns/init_freebsd.go for freesbd support

Start with vendor/github.com/docker/libnetwork/ns/init_linux.go and the FreeBSD build errors reported for init_freebsd.go, especially the missing syscall symbols. Run hack/make.sh on FreeBSD 11 to reproduce the failure, then verify that the libnetwork namespace package and the Docker build compile successfully for that platform.