Refactor layout to go-style, update deps

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

@@ -1,13 +0,0 @@
-// Copyright 2023 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.
-
-//go:build aix || darwin || dragonfly || freebsd || openbsd || solaris || zos
-
-package unix
-
-var mapper = &mmapper{
-	active: make(map[*byte][]byte),
-	mmap:   mmap,
-	munmap: munmap,
-}