[dia] Fix build w/o ENABLE_NLS

[Hans Breuer <hans src gnome org>]

commit cab4250658263f51c2cd8e4f9224c2ab19e5cf77
Author: Hans Breuer <hans breuer org>
Date:   Fri Sep 13 19:15:56 2013 +0200

    Fix build w/o ENABLE_NLS
    
    recent use of NC_ was not covered by Dia's own intl.h

 lib/intl.h |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/lib/intl.h b/lib/intl.h
index b19b8ab..324a631 100644
--- a/lib/intl.h
+++ b/lib/intl.h
@@ -8,6 +8,7 @@
 #else /* NLS is disabled */
 #  define _(String) (String)
 #  define N_(String) (String)
+#  define NC_(Context, String) (String)
 #  define gettext(String) (String)
 #  define textdomain(Domain)
 #  define bindtextdomain(Package, Directory)