[gobject-introspection] scanner: Fix use of undeclared variable in previous commit

[Colin Walters <walters src gnome org>]

commit e9939eeb1cd0a2626b968fd72387681366ecb61b
Author: Colin Walters <walters verbum org>
Date:   Thu Feb 7 15:25:25 2013 -0500

    scanner: Fix use of undeclared variable in previous commit
    
    Fixes the NetworkManager build.

 giscanner/transformer.py |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/giscanner/transformer.py b/giscanner/transformer.py
index 0858b8d..d6a5f8f 100644
--- a/giscanner/transformer.py
+++ b/giscanner/transformer.py
@@ -953,7 +953,7 @@ Note that type resolution may not succeed."""
         try:
             type_ = self.lookup_giname(typeval.target_giname)
         except KeyError:
-            typeval.target_giname = None
+            type_ = None
 
         if type_ is None:
             typeval.target_giname = None