os, syscall: add Statfs/Fstatfs stubs and Getpagesize for non-hosted targets

src/os/getpagesize.go

@@ -0,0 +1,6 @@
+package os
+
+import "syscall"
+
+// Getpagesize returns the underlying system's memory page size.
+func Getpagesize() int { return syscall.Getpagesize() }

src/os/types_anyos.go

@@ -6,11 +6,6 @@
 
 package os
 
-import "syscall"
-
-// Getpagesize returns the underlying system's memory page size.
-func Getpagesize() int { return syscall.Getpagesize() }
-
 func (fs *fileStat) Name() string { return fs.name }
 func (fs *fileStat) IsDir() bool  { return fs.Mode().IsDir() }
 

src/syscall/statfs_stubs.go

@@ -0,0 +1,39 @@
+//go:build baremetal || js || wasip1 || wasip2 || wasm_unknown || nintendoswitch
+
+// Copyright 2009 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.
+
+package syscall
+
+// Statfs_t and Fsid have been copied from the Go source tree
+// (syscall/ztypes_linux_amd64.go).
+
+type Statfs_t struct {
+	Type    int64
+	Bsize   int64
+	Blocks  uint64
+	Bfree   uint64
+	Bavail  uint64
+	Files   uint64
+	Ffree   uint64
+	Fsid    Fsid
+	Namelen int64
+	Frsize  int64
+	Flags   int64
+	Spare   [4]int64
+}
+
+type Fsid struct {
+	X__val [2]int32
+}
+
+// This is a stub, it is not functional.
+func Statfs(path string, buf *Statfs_t) (err error) {
+	return ENOSYS
+}
+
+// This is a stub, it is not functional.
+func Fstatfs(fd int, buf *Statfs_t) (err error) {
+	return ENOSYS
+}