mediatek: mt8192: supports mcusys off when system suspend

Change-Id: I0ea7f61085ea9ba26c580107ef0cb9940a25f5e2
diff --git a/plat/mediatek/mt8192/aarch64/platform_common.c b/plat/mediatek/mt8192/aarch64/platform_common.c
index eb1bb44..ffa10fe 100644
--- a/plat/mediatek/mt8192/aarch64/platform_common.c
+++ b/plat/mediatek/mt8192/aarch64/platform_common.c
@@ -19,6 +19,8 @@
 			MT_DEVICE | MT_RW | MT_SECURE),
 	MAP_REGION_FLAT(MTK_DEV_RNG2_BASE, MTK_DEV_RNG2_SIZE,
 			MT_DEVICE | MT_RW | MT_SECURE),
+	MAP_REGION_FLAT(MTK_MCDI_SRAM_BASE, MTK_MCDI_SRAM_MAP_SIZE,
+			MT_DEVICE | MT_RW | MT_SECURE),
 	{ 0 }
 };