[easytag] Fix check of unsigned duration type

[David King <davidk src gnome org>]

commit 9e60cbd498d6cf469c42cdd74419a7e8191eef06
Author: David King <amigadave amigadave com>
Date:   Fri May 17 00:21:11 2013 +0100

    Fix check of unsigned duration type
    
    Do not check for values less than 0, as the comparison is pointless for
    unsigned types.

 src/misc.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/misc.c b/src/misc.c
index 14428c8..d48593b 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -1100,7 +1100,7 @@ gchar *Convert_Duration (gulong duration)
     guint second=0;
     gchar *data = NULL;
 
-    if (duration<=0)
+    if (duration == 0)
         return g_strdup_printf("%d:%.2d",minute,second);
 
     hour   = duration/3600;