[pan2] compile fix for gnutls (dtor VerifyData)

[Heinrich MÃller <henmull src gnome org>]

commit 9ab2649d036da993d3ac0d705fe3b0974ec9e79f
Author: Heinrich MÃlller <henmull src gnome org>
Date:   Thu May 3 17:26:09 2012 +0200

    compile fix for gnutls (dtor VerifyData)

 pan/gui/gui.h |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)
---
diff --git a/pan/gui/gui.h b/pan/gui/gui.h
index 8e11675..0a529ea 100644
--- a/pan/gui/gui.h
+++ b/pan/gui/gui.h
@@ -74,7 +74,11 @@ namespace pan
         std::string cert_name;
         int nr;
         GUI* gui;
-        ~VerifyData() { gnutls_x509_crt_deinit(cert); }
+        ~VerifyData() {
+#ifdef HAVE_GNUTLS
+            gnutls_x509_crt_deinit(cert);
+#endif
+        }
       };
 
     public: // ActionManager