mediatek: mt8192: Add CPU hotplug and MCDI support

Implement PSCI platform OPs to support CPU hotplug and MCDI.

Change-Id: I31abfc752b69ac40e70bc9e7a55163eb39776c44
diff --git a/plat/mediatek/mt8192/plat_topology.c b/plat/mediatek/mt8192/plat_topology.c
index aa4975e..8c1231a 100644
--- a/plat/mediatek/mt8192/plat_topology.c
+++ b/plat/mediatek/mt8192/plat_topology.c
@@ -17,6 +17,8 @@
 	/* Number of root nodes */
 	PLATFORM_SYSTEM_COUNT,
 	/* Number of children for the root node */
+	PLATFORM_MCUSYS_COUNT,
+	/* Number of children for the mcusys node */
 	PLATFORM_CLUSTER_COUNT,
 	/* Number of children for the first cluster node */
 	PLATFORM_CLUSTER0_CORE_COUNT,