user32: Use the message_data_t union when receiving a message.
diff --git a/server/protocol.def b/server/protocol.def
index 6d6be5b..b989472 100644
--- a/server/protocol.def
+++ b/server/protocol.def
@@ -218,6 +218,7 @@
 typedef union
 {
     unsigned char            bytes[1];   /* raw data for sent messages */
+    struct hardware_msg_data hardware;
     struct callback_msg_data callback;
     struct winevent_msg_data winevent;
 } message_data_t;