Add framework_path module

This allows scripts in the scripts/ directory to get the path to the
mbedtls_framework module in framework/scripts/

Signed-off-by: David Horstmann <david.horstmann@arm.com>
diff --git a/scripts/generate_psa_constants.py b/scripts/generate_psa_constants.py
index 119a632..b20bae1 100755
--- a/scripts/generate_psa_constants.py
+++ b/scripts/generate_psa_constants.py
@@ -17,6 +17,7 @@
 import os
 import sys
 
+import framework_path # pylint: disable=unused-import
 from mbedtls_framework import build_tree
 from mbedtls_framework import macro_collector