Fix inconsistent #include style

Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
diff --git a/clients/image.c b/clients/image.c
index 51ce1f0..13115d2 100644
--- a/clients/image.c
+++ b/clients/image.c
@@ -33,7 +33,7 @@
 #include <glib.h>
 #include <gdk-pixbuf/gdk-pixbuf.h>
 
-#include "wayland-client.h"
+#include <wayland-client.h>
 
 #include "window.h"