[gthumb] do not use the timezone variable when it's not defined

[Paolo Bacchilega <paobac src gnome org>]

commit da244e7e7e597091a59a1508dbfc9c0ec1e52419
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Thu Dec 29 22:35:16 2011 +0100

    do not use the timezone variable when it's not defined
    
    pointed out by Pav Lucistnik

 gthumb/glib-utils.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)
---
diff --git a/gthumb/glib-utils.c b/gthumb/glib-utils.c
index cf0536f..4100212 100644
--- a/gthumb/glib-utils.c
+++ b/gthumb/glib-utils.c
@@ -525,9 +525,8 @@ _g_time_val_to_exif_date (GTimeVal *time_)
 static int
 _g_time_get_timezone_offset (struct tm *tm)
 {
-	int offset;
+	int offset = 0;
 
-	offset = -timezone;
 #if defined (HAVE_TM_GMTOFF)
 	offset = tm->tm_gmtoff;
 #elif defined (HAVE_TIMEZONE)