[gnome-session] main: add #include <locale.h> one more time

[Ray Strode <halfline src gnome org>]

commit 6277bd5d94f94f6be38bc2ff54e290ecae209e79
Author: Ray Strode <rstrode redhat com>
Date:   Thu Jan 21 10:05:22 2016 -0500

    main: add #include <locale.h> one more time
    
    Fixes build.

 tools/gnome-session-quit.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/tools/gnome-session-quit.c b/tools/gnome-session-quit.c
index a83f4fe..76b6f6d 100644
--- a/tools/gnome-session-quit.c
+++ b/tools/gnome-session-quit.c
@@ -20,6 +20,7 @@
 
 #include <config.h>
 
+#include <locale.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <stdio.h>