replace platform conditions with os_posix and os_bsd where applicable

third_party/iccjpeg/iccjpeg.gyp

 # Copyright (c) 2011 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.
 
 {
   'targets': [
     {
       'target_name': 'iccjpeg',
       'type': 'static_library',
       'dependencies': [
         '<(libjpeg_gyp_path):libjpeg',
       ],
       'sources': [
         'iccjpeg.c',
         'iccjpeg.h',
       ],
       'conditions': [
-        ['OS=="openbsd" and use_system_libjpeg==1', {
+        ['os_bsd==1 and use_system_libjpeg==1', {
           'include_dirs': [
             '/usr/local/include',
           ],
         }],
       ],
       'direct_dependent_settings': {
         'include_dirs': [
           '.',
         ],
       },
     },
   ],
 }