Fix dependencies

vendor/golang.org/x/sys/unix/env_unix.go

@@ -1,31 +0,0 @@
-// Copyright 2010 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
-
-// Unix environment variables.
-
-package unix
-
-import "syscall"
-
-func Getenv(key string) (value string, found bool) {
-	return syscall.Getenv(key)
-}
-
-func Setenv(key, value string) error {
-	return syscall.Setenv(key, value)
-}
-
-func Clearenv() {
-	syscall.Clearenv()
-}
-
-func Environ() []string {
-	return syscall.Environ()
-}
-
-func Unsetenv(key string) error {
-	return syscall.Unsetenv(key)
-}