PNaCl dynamic loading: Extend pnacl-translate to be able to translate PSOs

tests/pnacl_dynamic_loading/test_pso.c

+/*
+ * Copyright (c) 2014 The Native Client Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+static int var = 2345;
+
+static int example_func(int *ptr) {
+  return *ptr + 1234;
+}
+
+static int *get_var(void) {
+  /* Test use of -fPIC by getting an address. */
+  return &var;
+}
+
+struct pso_root {
+  int (*example_func)(int *ptr);
+  int *(*get_var)(void);
+};
+
+struct pso_root __pnacl_pso_root = {
+  example_func,
+  get_var,
+};