[1.1.X] Fixed a silly bug in [12644].

Backport of [12646].

Of course, this sort of thing *does* do wonders for my commit count.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@12647 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/formtools/wizard.py

@@ -31,7 +31,7 @@ class FormWizard(object):
         self.initial = initial or {}
 
         # Dictionary of extra template context variables.
-        extra_context = {}
+        self.extra_context = {}
 
         # A zero-based counter keeping track of which step we're in.
         self.step = 0