Fix bootstrap on windows

recipes.py

Index: recipes.py
diff --git a/recipes.py b/recipes.py
index e71420e5d7307ac9d5dd5150456cccecbcdbc05e..092917380efe1d30abd991da98930ddf020def73 100755
--- a/recipes.py
+++ b/recipes.py
@@ -12,6 +12,7 @@ infra/config/recipes.cfg.
 import argparse
 import json
 import logging
+import platform
 import os
 import subprocess
 import sys
@@ -390,10 +391,11 @@ def main():
 
     os.environ['RECIPES_RUN_BOOTSTRAP'] = '1'
     args = sys.argv
-    return subprocess.call(
-        [os.path.join(
-            os.path.dirname(os.path.realpath(__file__)), 'ENV/bin/python'),
-         os.path.join(ROOT_DIR, 'recipes.py')] + original_sys_argv[1:])
+    executable = ('python.exe' if sys.platform.lower() in (
+            'win32', 'cygwin') else 'python')
+    return subprocess.call([os.path.join(
+      ROOT_DIR, 'ENV', 'bin', executable),
+      os.path.join(ROOT_DIR, 'recipes.py')] + original_sys_argv[1:])
 
   if args.verbose:
     logging.getLogger().setLevel(logging.INFO)