feat(nxp/layerscape): add build configs for layerscape platforms

This patch adds build configs and corresponding test configs for ls1028ardb,
lx2160ardb, lx2160aqds and lx2162aqds platforms.

Signed-off-by: Jiafei Pan <Jiafei.Pan@nxp.com>
Change-Id: Id0c7b52e2e25fdf87286ca3ace41f31111109fd3
diff --git a/group/tf-l1-build-plat/lx2160ardb-default:nil b/group/tf-l1-build-plat/lx2160ardb-default:nil
new file mode 100644
index 0000000..45065d8
--- /dev/null
+++ b/group/tf-l1-build-plat/lx2160ardb-default:nil
@@ -0,0 +1,6 @@
+#
+# Copyright (c) 2021 Arm Limited. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+