Add definition of an event send from a nano app to host.

Bug: 28273520
Change-Id: I4d5f7a6a844d542078a69155f166b0a7b0bc814c
diff --git a/include/hardware/context_hub.h b/include/hardware/context_hub.h
index 4b47b64..a4ae0c2 100644
--- a/include/hardware/context_hub.h
+++ b/include/hardware/context_hub.h
@@ -373,7 +373,7 @@
     CONTEXT_HUB_QUERY_MEMORY = 6, // Query for memory info
 } hub_messages_e;
 
-#define CONTEXT_HUB_TYPE_PRIVATE_MSG_BASE 0x10000
+#define CONTEXT_HUB_TYPE_PRIVATE_MSG_BASE 0x00400
 
 /**
  * A callback registers with the context hub service to pass messages