mboxd: Broadcast the daemon is ready on all transports

The code as it stood only sent the state update at startup on the active
transport, which is somewhat arbitrarily chosen as an implementation
detail of the mbox initialisation function.

If the host firmware is using IPMI, it will not learn of the update
unless it attempts to contact mboxd, which it won't do if it knows the
daemon isn't there, which it may have learned of by receiving a state
update from the daemon's shutdown path. In this circumstance the host
firmware is now stuck.

Relieve the host firmware of this problem by always sending the daemon
state on all supported transports. To avoid some insanity we introduce a
new callback in struct transport_ops that allows use to send the BMC's
entire event state rather than just set or clear updates.

Change-Id: I094ff4089eeebd8be99fbd343b94f7bbef023fb1
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/transport_dbus.h b/transport_dbus.h
index 6f93f35..ec9a13c 100644
--- a/transport_dbus.h
+++ b/transport_dbus.h
@@ -5,8 +5,10 @@
 #define TRANSPORT_DBUS_H
 
 #include "dbus.h"
+#include "transport.h"
 
-int transport_dbus_init(struct mbox_context *context);
+int transport_dbus_init(struct mbox_context *context,
+			const struct transport_ops **ops);
 void transport_dbus_free(struct mbox_context *context);
 
 #endif /* TRANSPORT_DBUS_H */