[libdazzle] build: remove unused file

[Christian Hergert <chergert src gnome org>]

commit 2e1fd4417c0a6827c8ae588b3e2c0c870878e1e9
Author: Christian Hergert <chergert redhat com>
Date:   Sun Jun 18 23:43:33 2017 -0700

    build: remove unused file

 src/graphing/dzl-column-private.h |   49 -------------------------------------
 src/meson.build                   |    1 -
 2 files changed, 0 insertions(+), 50 deletions(-)
---
diff --git a/src/meson.build b/src/meson.build
index 0017ae2..34d0d58 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -339,7 +339,6 @@ libdazzle_sources = [
   'animation/dzl-frame-source.c',
   'animation/dzl-frame-source.h',
 
-  'graphing/dzl-column-private.h',
   'graphing/dzl-graph-column-private.h',
 
   'panel/dzl-dock-bin-edge-private.h',