Use attributes rather than header for legacy memory sharing.

This removes the architected message header.

Bug: 132420445
Change-Id: Id568f379be194bca552506a470355c018a611c2b
diff --git a/inc/hf/spci_internal.h b/inc/hf/spci_internal.h
index 1382669..1fc226f 100644
--- a/inc/hf/spci_internal.h
+++ b/inc/hf/spci_internal.h
@@ -63,6 +63,5 @@
 
 struct spci_value spci_msg_handle_architected_message(
 	struct vm_locked to_locked, struct vm_locked from_locked,
-	const struct spci_architected_message_header
-		*architected_message_replica,
-	uint32_t size, struct mpool *api_page_pool);
+	struct spci_memory_region *memory_region, uint32_t size,
+	uint32_t attributes, struct mpool *api_page_pool);