[shotwell] facedetect: Clean-up includes

[Jens Georg <jensgeorg src gnome org>]

commit 46220fc66ef896db3c9ec0eed9d010beb903d1e8
Author: Jens Georg <mail jensge org>
Date:   Thu Oct 11 11:46:00 2018 +0200

    facedetect: Clean-up includes
    
    We don't need highgui just to open an image

 facedetect/shotwell-facedetect.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/facedetect/shotwell-facedetect.cpp b/facedetect/shotwell-facedetect.cpp
index 1b093797..aa16f801 100644
--- a/facedetect/shotwell-facedetect.cpp
+++ b/facedetect/shotwell-facedetect.cpp
@@ -7,9 +7,9 @@
  * See the COPYING file in this distribution.
  */
 
-#include "opencv2/objdetect/objdetect.hpp"
-#include "opencv2/highgui/highgui.hpp"
-#include "opencv2/imgproc/imgproc.hpp"
+#include <opencv2/objdetect/objdetect.hpp>
+#include <opencv2/imgproc/imgproc.hpp>
+#include <opencv2/imgcodecs/imgcodecs.hpp>
 
 #include <iostream>
 #include <stdio.h>