Fixed Spelling mistake

lp bug: https://launchpad.net/bugs/483527 fixed

bzr revid: hda@tinyerp.com-20091116113710-ixwxro0bweezjbre

bin/osv/orm.py

@@ -1589,7 +1589,7 @@ class orm_memory(orm_template):
 
         # get the default values from the context
         for key in context or {}:
-            if key.startswith('default_') and (key[8:] in fieds_list):
+            if key.startswith('default_') and (key[8:] in fields_list):
                 value[key[8:]] = context[key]
         return value