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

SGI-Clark platform is the next version in the Arm's SGI platform
series. One of the primary difference between the SGI-575 platform and
the SGI-Clark platform is the MHU version (MHUv2 in case of SGI-Clark).
Add the required base support for SGI-Clark platform.

Change-Id: If396e5279fdf801d586662dad0b55195e81371e4
Signed-off-by: Chandni Cherukuri <chandni.cherukuri@arm.com>
diff --git a/plat/arm/css/sgi/sgi_image_load.c b/plat/arm/css/sgi/sgi_image_load.c
index 52dcf88..d97583e 100644
--- a/plat/arm/css/sgi/sgi_image_load.c
+++ b/plat/arm/css/sgi/sgi_image_load.c
@@ -50,6 +50,10 @@
 		platid = mmio_read_32(SSC_VERSION) & SSC_VERSION_PART_NUM_MASK;
 		platcfg = (mmio_read_32(SSC_VERSION) >> SSC_VERSION_CONFIG_SHIFT)
 				& SSC_VERSION_CONFIG_MASK;
+	} else if (strcmp(platform_name, "arm,sgi-clark") == 0) {
+		platid = mmio_read_32(SID_REG_BASE + SID_SYSTEM_ID_OFFSET)
+				& SID_SYSTEM_ID_PART_NUM_MASK;
+		platcfg = mmio_read_32(SID_REG_BASE + SID_SYSTEM_CFG_OFFSET);
 	} else {
 		WARN("Invalid platform\n");
 		return -1;