A small fix from snuffy

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@90746 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/hashtab.c

@@ -534,7 +534,7 @@ static void *ast_hashtab_lookup_internal(struct ast_hashtab *tab, const void *ob
 		}
 	}
 
-	return 0;
+	return NULL;
 }
 
 void ast_hashtab_get_stats( struct ast_hashtab *tab, int *biggest_bucket_size, int *resize_count, int *num_objects, int *num_buckets)