[goffice] Fixed warning.

[Jean Bréfort <jbrefort src gnome org>]

commit 8ad0bb30fea47945171b61296454af51a9b06253
Author: Jean Brefort <jean brefort normalesup org>
Date:   Thu May 29 21:05:06 2014 +0200

    Fixed warning.

 goffice/utils/go-unit.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/goffice/utils/go-unit.c b/goffice/utils/go-unit.c
index 51a01c4..556797c 100644
--- a/goffice/utils/go-unit.c
+++ b/goffice/utils/go-unit.c
@@ -32,7 +32,7 @@ struct _GoUnit {
        unsigned Id;
 };
 
-static unsigned last_unit = GO_UNIT_MAX;
+static int last_unit = GO_UNIT_MAX;
 
 GoUnit units[GO_UNIT_MAX] = {
        {(char *) "m", (char *) "L", 1., GO_UNIT_METER},