[glom] Use std::strfime() instead of strftime.

[Murray Cumming <murrayc src gnome org>]

commit b5b3d30c00471fd52084d5f8dd62a2e38b185fe6
Author: Murray Cumming <murrayc murrayc com>
Date:   Tue Sep 1 14:13:13 2015 +0200

    Use std::strfime() instead of strftime.

 glom/libglom/data_structure/glomconversions.cc |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/glom/libglom/data_structure/glomconversions.cc b/glom/libglom/data_structure/glomconversions.cc
index c1988ce..62455f2 100644
--- a/glom/libglom/data_structure/glomconversions.cc
+++ b/glom/libglom/data_structure/glomconversions.cc
@@ -309,7 +309,7 @@ Glib::ustring Conversions::format_tm(const tm& tm_data, const std::locale& local
     // Set the first byte to something other than '\0', to be able to
     // recognize whether strftime actually failed or just returned "".
     buf.get()[0] = '\1';
-    const auto len = strftime(buf.get(), bufsize, locale_format.c_str(), &tm_data);
+    const auto len = std::strftime(buf.get(), bufsize, locale_format.c_str(), &tm_data);
 
     if(len != 0 || buf.get()[0] == '\0')
     {