[NaCl SDK] nacl_io: Fix inet_ntop to be consistent with glibc.

native_client_sdk/src/libraries/nacl_io/syscalls/inet_ntoa.c

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "nacl_io/ossocket.h"
+
 #if defined(PROVIDES_SOCKET_API) && !defined(__GLIBC__)
 
-#include <string.h>
-#include "sdk_util/macros.h"
-
 static uint8_t GetByte(const void* addr, int byte) {
-  const char* buf = static_cast<const char*>(addr);
-  return static_cast<uint8_t>(buf[byte]);
+  const char* buf = (const char*)addr;
+  return (uint8_t)buf[byte];
 }
 
-EXTERN_C_BEGIN
-
 char* inet_ntoa(struct in_addr in) {
   static char addr[INET_ADDRSTRLEN];
   snprintf(addr, INET_ADDRSTRLEN, "%u.%u.%u.%u",
            GetByte(&in, 0), GetByte(&in, 1),
            GetByte(&in, 2), GetByte(&in, 3));
   return addr;
 }
 
-EXTERN_C_END
-
 #endif  // defined(PROVIDES_SOCKET_API) && !defined(__GLIBC__)