dbus: Use consistent prefix for dbus function symbols

Improves readability by making it easier to tell at a glance what the
symbols are affecting.

Change-Id: I00e206b6383670118232e9b5a48cfbc4be5775b8
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/mboxd_dbus.h b/mboxd_dbus.h
index beb5790..500c25b 100644
--- a/mboxd_dbus.h
+++ b/mboxd_dbus.h
@@ -4,7 +4,7 @@
 #ifndef MBOXD_DBUS_H
 #define MBOXD_DBUS_H
 
-int init_mboxd_dbus(struct mbox_context *context);
-void free_mboxd_dbus(struct mbox_context *context);
+int mboxd_dbus_init(struct mbox_context *context);
+void mboxd_dbus_free(struct mbox_context *context);
 
 #endif /* MBOXD_DBUS_H */