[gtk+] gtk/Makefile.am: Fix 'make dist'

[Chun-wei Fan <fanchunwei src gnome org>]

commit d15712fc9bbef5efcfc4fb8126541b213a680c20
Author: Chun-wei Fan <fanchunwei src gnome org>
Date:   Mon Jun 12 18:14:57 2017 +0800

    gtk/Makefile.am: Fix 'make dist'
    
    We don't have gtkcenterboxprivate.h anymore, as it became a public
    header...

 gtk/Makefile.am |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)
---
diff --git a/gtk/Makefile.am b/gtk/Makefile.am
index 82c725f..d204ba2 100644
--- a/gtk/Makefile.am
+++ b/gtk/Makefile.am
@@ -578,8 +578,7 @@ gtk_private_h_sources =             \
        gtkwindowprivate.h      \
        gtktreemenu.h           \
        gdkpixbufutilsprivate.h \
-       gtkgizmoprivate.h \
-       gtkcenterboxprivate.h
+       gtkgizmoprivate.h
 
 # GTK+ C sources to build the library from
 gtk_base_c_sources =           \