build(versal-net): add build config for ddr

Add build config for Versal NET platform.
The TF-A is placed and executed from DDR in this scenario.

Signed-off-by: Akshay Belsare <akshay.belsare@amd.com>
Change-Id: I44df99a9cdd0cdab53bf9005bf5b52da170f8680
diff --git a/group/tf-l1-build-plat/versal_net-ddr:nil b/group/tf-l1-build-plat/versal_net-ddr:nil
new file mode 100644
index 0000000..53e6143
--- /dev/null
+++ b/group/tf-l1-build-plat/versal_net-ddr:nil
@@ -0,0 +1,6 @@
+#
+# Copyright (c) 2023, Advanced Micro Devices, Inc. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+