Revert of Run pkg-config for Udev only if use_udev==1

build/linux/system.gyp

 # Copyright (c) 2012 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.
 
 {
   'variables': {
     'conditions': [
       ['sysroot!=""', {
         'pkg-config': '<(chroot_cmd) ./pkg-config-wrapper "<(sysroot)" "<(target_arch)" "<(system_libdir)"',
       }, {
@@ skipping 1015 matching lines @@
             }],
           ]
         }],
       ],
     },
     {
       'target_name': 'udev',
       'type': 'none',
       'conditions': [
         # libudev is not available on *BSD
-        ['_toolset=="target" and os_bsd!=1 and use_udev==1', {
+        ['_toolset=="target" and os_bsd!=1', {
           'direct_dependent_settings': {
             'cflags': [
               '<!@(<(pkg-config) --cflags libudev)'
             ],
           },
           'link_settings': {
             'ldflags': [
               '<!@(<(pkg-config) --libs-only-L --libs-only-other libudev)',
             ],
             'libraries': [
               '<!@(<(pkg-config) --libs-only-l libudev)',
             ],
           },
         }],
       ],
     },
   ],
 }