Change to os.path functions base on comment

Signed-off-by: Xiaokang Qian <xiaokang.qian@arm.com>
diff --git a/scripts/generate_driver_wrappers.py b/scripts/generate_driver_wrappers.py
index ba5c4c2..e0f2827 100755
--- a/scripts/generate_driver_wrappers.py
+++ b/scripts/generate_driver_wrappers.py
@@ -72,7 +72,7 @@
 
     result = render(driver_wrapper_template_filename, driver_jsoncontext)
 
-    with open(file=os.path.join(output_dir, template_file_name.rsplit(".", 1)[0]),
+    with open(file=os.path.join(output_dir, os.path.splitext(template_file_name)[0]),
               mode='w',
               encoding='UTF-8') as out_file:
         out_file.write(result)