compiler: build separation runtime with clite

runtime/internal/lib/os/exec/unix_eaccess_linux.go

@@ -0,0 +1,15 @@
+// Copyright 2022 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 exec
+
+import (
+	"syscall"
+
+	"github.com/goplus/llgo/runtime/internal/clite/syscall/unix"
+)
+
+func unixEaccess(path string, mode uint32) error {
+	return syscall.Faccessat(unix.AT_FDCWD, path, mode, unix.AT_EACCESS)
+}