plat/arm/sgi: add support for SGI-Clark.Ares platform

SGI-Clark.Ares platform is a variant of the SGI-Clark platform. It has
two clusters of four Ares CPUs each. Though very similar to the SGI575
platform, there are subtle differences. HW_CONFIG and TB_FW_CONFIG dts
files have been added.

Change-Id: I740a33cbd1c3b1f1984cb56243b46ad379bab3e6
Signed-off-by: Chandni Cherukuri <chandni.cherukuri@arm.com>
diff --git a/plat/arm/board/sgiclarka/fdts/sgiclarka.dts b/plat/arm/board/sgiclarka/fdts/sgiclarka.dts
new file mode 100644
index 0000000..43bd856
--- /dev/null
+++ b/plat/arm/board/sgiclarka/fdts/sgiclarka.dts
@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/dts-v1/;
+/ {
+	/* compatible string */
+	compatible = "arm,sgi-clark";
+
+	/*
+	 * Place holder for system-id node with default values. The
+	 * value of platform-id and config-id will be set to the
+	 * correct values during the BL2 stage of boot.
+	 */
+	system-id {
+		platform-id = <0x0>;
+		config-id = <0x0>;
+	};
+};