[goffice] Compilation: fix warnings.

[Morten Welinder <mortenw src gnome org>]

commit da0981dc37ad6311307789ad643715957cdd1e44
Author: Morten Welinder <terra gnome org>
Date:   Fri Aug 5 11:22:05 2011 -0400

    Compilation: fix warnings.

 plugins/plot_distrib/gog-histogram.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/plugins/plot_distrib/gog-histogram.h b/plugins/plot_distrib/gog-histogram.h
index a4f0f8f..2736722 100644
--- a/plugins/plot_distrib/gog-histogram.h
+++ b/plugins/plot_distrib/gog-histogram.h
@@ -31,7 +31,7 @@ typedef struct {
 
 	struct {
 		double minima, maxima;
-		GOFormat *fmt;
+		GOFormat const *fmt;
 		GODateConventions const *date_conv;
 	} x, y;
 	gboolean vertical;