plat/arm/sgi: add platform id value for rdn2 platform

In preparation for adding the board support for RD-N2 platform, add
macros to define the platform id and the corresponding SCMI platform
info for the RD-N2 platform.

Change-Id: Ie764ae618732b39e316f7ed080421f5d79adab21
Signed-off-by: Aditya Angadi <aditya.angadi@arm.com>

plat/arm/css/sgi/include/sgi_variant.h

@@ -17,6 +17,9 @@
 /* SID Version values for RD-Daniel */
 #define RD_DANIEL_SID_VER_PART_NUM		0x078a
 
+/* SID Version values for RD-N2 */
+#define RD_N2_SID_VER_PART_NUM			0x07B7
+
 /* Structure containing SGI platform variant information */
 typedef struct sgi_platform_info {
 	unsigned int platform_id;	/* Part Number of the platform */

plat/arm/css/sgi/sgi_bl31_setup.c

@@ -74,7 +74,8 @@ static scmi_channel_plat_info_t rd_n1e1_edge_scmi_plat_info[] = {
 scmi_channel_plat_info_t *plat_css_get_scmi_info(int channel_id)
 {
 	if (sgi_plat_info.platform_id == RD_N1E1_EDGE_SID_VER_PART_NUM ||
-		sgi_plat_info.platform_id == RD_DANIEL_SID_VER_PART_NUM) {
+		sgi_plat_info.platform_id == RD_DANIEL_SID_VER_PART_NUM ||
+		sgi_plat_info.platform_id == RD_N2_SID_VER_PART_NUM) {
 		if (channel_id >= ARRAY_SIZE(rd_n1e1_edge_scmi_plat_info))
 			panic();
 		return &rd_n1e1_edge_scmi_plat_info[channel_id];