scripts: Port codegen script from VVL
diff --git a/scripts/common_codegen.py b/scripts/common_codegen.py
index 8954532..d56ebac 100644
--- a/scripts/common_codegen.py
+++ b/scripts/common_codegen.py
@@ -18,10 +18,7 @@
 #
 # Author: Mark Lobodzinski <mark@lunarg.com>
 
-import os,re,sys,string
-import xml.etree.ElementTree as etree
-from generator import *
-from collections import namedtuple
+import os
 
 # Copyright text prefixing all headers (list of strings).
 prefixStrings = [
@@ -71,3 +68,7 @@
     if platform is not None:
         protect = platform_dict[platform]
     return protect
+
+# helper to define paths relative to the repo root
+def repo_relative(path):
+    return os.path.abspath(os.path.join(os.path.dirname(__file__), '..', path))