overlay: Auatomatically mount debugfs

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/overlay/debugfs.h b/overlay/debugfs.h
new file mode 100644
index 0000000..52577ef
--- /dev/null
+++ b/overlay/debugfs.h
@@ -0,0 +1 @@
+int debugfs_init(void);