ARM platforms: Add support for SGI575

Add support for System Guidance for Infrastructure platform SGI575.

Change-Id: I0125c2ed4469fbc8367dafcc8adce770b6b3147d
Signed-off-by: Nariman Poushin <nariman.poushin@linaro.org>
diff --git a/plat/arm/css/sgi/sgi_security.c b/plat/arm/css/sgi/sgi_security.c
new file mode 100644
index 0000000..23e1a64
--- /dev/null
+++ b/plat/arm/css/sgi/sgi_security.c
@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arm_config.h>
+#include <plat_arm.h>
+
+/*
+ * We assume that all security programming is done by the primary core.
+ */
+void plat_arm_security_setup(void)
+{
+}