Remove "AV Win7" bot.

build/masters/master.chromium.perf_av/slaves.cfg

 # -*- python -*-
 # ex: set syntax=python:
 
 # 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.
 
 # See master.experimental/slaves.cfg for documentation.
 
 slaves = [
   {
     'master': 'ChromiumPerfAv',
     'hostname': 'chromeperf17',
     'builder': 'AV Linux',
     'os': 'linux',
     'version': 'precise',
     'bits': '64',
   },
   {
     'master': 'ChromiumPerfAv',
     'hostname': 'chromeperf18',
     'builder': 'AV Linux Builder',
     'os': 'linux',
     'version': 'precise',
     'bits': '64',
   },
-  {
-    'master': 'ChromiumPerfAv',
-    'hostname': 'chromeperf33',

[Nico, 2013/12/13 23:09:09]

(btw, masters/master.chromium.unused is gone – is there a list of free slaves
somewhere these days, or do i just delete this?)

[ghost stip (do not use), 2013/12/13 23:57:09]

I thought it was still there, I'll ask the sysadmins what's up

-    'builder': 'AV Win7',
-    'os': 'win',
-    'version': 'Win7',
-    'bits': '64',
-  },
 ]