[gtk/a11y/atspi] Fix the build

[Matthias Clasen <matthiasc src gnome org>]

commit 8f63443393cdeeab38d9de000ee59b93fdbbde4d
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Oct 12 16:40:34 2020 -0400

    Fix the build

 gtk/a11y/gtkatspiroot.c | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/gtk/a11y/gtkatspiroot.c b/gtk/a11y/gtkatspiroot.c
index 3e938d3fa1..75290623ea 100644
--- a/gtk/a11y/gtkatspiroot.c
+++ b/gtk/a11y/gtkatspiroot.c
@@ -23,6 +23,7 @@
 #include "gtkatspirootprivate.h"
 
 #include "gtkatspicontextprivate.h"
+#include "gtkaccessibleprivate.h"
 #include "gtkatspiprivate.h"
 #include "gtkatspiutilsprivate.h"