winvbox.py: remove unused variable

util/winvbox.py

@@ -35,6 +35,7 @@ winvbox.py assumes Python is located at "C:/Python<VER>/python.exe".
 Instead of using --machine option, you can also add word "gevent" to the machine description in
 order to be selected by this script.
 """
+
 import sys
 import os
 import re
@@ -43,8 +44,6 @@ import datetime
 import glob
 from functools import wraps
 
-WINVBOX_LOG = 'winvbox.log'
-
 
 def main():
     import optparse