checks: Set the source in HashesCheck correctly

Instead of setting the source within a for loop, set it outside, so it
does what it is supposed to do, instead of accidentally working
because self has a source field set too.
Signed-off-by: NGergely Nagy <algernon@madhouse-project.org>

daklib/checks.py

@@ -162,7 +162,7 @@ class HashesCheck(Check):
         changes = upload.changes
         for f in changes.files.itervalues():
             f.check(upload.directory)
-            source = changes.source
+        source = changes.source
         if source is not None:
             for f in source.files.itervalues():
                 f.check(upload.directory)