Use new-style return values from spci_msg_wait and spci_msg_poll.

Bug: 141469322
Change-Id: Ib9815695537837f029c698c6966bad93c094e89e
diff --git a/src/arch/aarch64/hypervisor/handler.c b/src/arch/aarch64/hypervisor/handler.c
index 26b5496..d58a600 100644
--- a/src/arch/aarch64/hypervisor/handler.c
+++ b/src/arch/aarch64/hypervisor/handler.c
@@ -320,10 +320,10 @@
 		args->func = api_spci_msg_send(args->arg1, current(), next);
 		return true;
 	case SPCI_MSG_WAIT_32:
-		args->func = api_spci_msg_recv(true, current(), next);
+		*args = api_spci_msg_recv(true, current(), next);
 		return true;
 	case SPCI_MSG_POLL_32:
-		args->func = api_spci_msg_recv(false, current(), next);
+		*args = api_spci_msg_recv(false, current(), next);
 		return true;
 	}